Given: ABCD is a quadrilateral, BC║AD, m∠ A = 90°

Prove: BD^2 − AC^2 = AD^2 − BC^2

Please Help!!! I need this for tonight!!

Answers

Answer 1

Answer:

  Rearrange the equations that result from use of the Pythagorean theorem.

Step-by-step explanation:

Transversal AB crossing parallel lines AD and BC makes supplementary interior same-side angles A and B. Since A = 90°, B must be 90°. The Pythagorean theorem then applies in the right triangles ABC and ABD.

We can use that theorem to write two expressions for AB^2:

  BD^2 -AD^2 = AB^2 = AC^2 -BC^2

The middle expression, AB^2, isn't needed beyond this point. Adding (AD^2 -AC^2) to both sides of the equation gives the desired result:

  BD^2 -AC^2 = AD^2 -BC^2


Related Questions

Find the area of the shape
with the radius of 10

Answers

Answer: 314.16

Step-by-step explanation: To find the area of a circle you have to square the radius then multiply by pi. 10 squared is 100 then multiplied by pi is 314.16 (rounded to the nearest hundredth).



Determine the y-intercept of the function.
x = 4y - 6

Answers

Answer:

y = 3/2

Step-by-step explanation:

Answer:

x=4y-6  

Geometric figure: Straight Line

 Slope = 0.500/2.000 = 0.250

 x-intercept = -6/1 = -6.00000

 y-intercept = 6/4 = 3/2 = 1.50000

Rearrange:

Rearrange the equation by subtracting what is to the right of the equal sign from both sides of the equation :

                    x-(4*y-6)=0  

Step by step solution :

Step  1  :

Equation of a Straight Line

1.1     Solve   x-4y+6  = 0

Tiger recognizes that we have here an equation of a straight line. Such an equation is usually written y=mx+b ("y=mx+c" in the UK).

"y=mx+b" is the formula of a straight line drawn on Cartesian coordinate system in which "y" is the vertical axis and "x" the horizontal axis.

In this formula :

y tells us how far up the line goes

x tells us how far along

m is the Slope or Gradient i.e. how steep the line is

b is the Y-intercept i.e. where the line crosses the Y axis

The X and Y intercepts and the Slope are called the line properties. We shall now graph the line  x-4y+6  = 0 and calculate its properties

Graph of a Straight Line :

 

 

Calculate the Y-Intercept :

Notice that when x = 0 the value of y is 3/2 so this line "cuts" the y axis at y= 1.50000

 y-intercept = 6/4 = 3/2  =  1.50000  

Calculate the X-Intercept :

When y = 0 the value of x is -6/1 Our line therefore "cuts" the x axis at x=-6.00000

 x-intercept = -6/1  = -6.00000  

Calculate the Slope :

Slope is defined as the change in y divided by the change in x. We note that for x=0, the value of y is 1.500 and for x=2.000, the value of y is 2.000. So, for a change of 2.000 in x (The change in x is sometimes referred to as "RUN") we get a change of 2.000 - 1.500 = 0.500 in y. (The change in y is sometimes referred to as "RISE" and the Slope is m = RISE / RUN)

   Slope     =  0.500/2.000 =  0.250  

Geometric figure: Straight Line

 Slope = 0.500/2.000 = 0.250

 x-intercept = -6/1 = -6.00000

 y-intercept = 6/4 = 3/2 = 1.50000

Step-by-step explanation:

A friendly contest involves randomly drawing a marble from a bag that contains 16 blue marbles, 12 red
marbles, and 8 yellow marbles. If a blue marble is drawn, Nathan wins. If a red marble is drawn, Taylor wins.
If a yellow marble is drawn, Cady wins.
Who is most likely to win the contest?
1 Nathan
2 Cady
3 They are equally likely to win.
4 Taylor

Answers

Answer: I have a huge feeling it would be Nathan because he has the most blue marble. Yk?

This includes the interest you will have to pay to a lender beyond the amount you need to purchase the car:


a) Lease Origination Fee

b) Transaction Fees

c) Finance Charges

d) Down Payment

Submit

Answers

Answer:

c) Finance Charges

Step-by-step explanation:

-Lease Origination Fee  is a fee that a financial institution charges for processing a loan request.

-Transaction Fees  are the fees that have to be paid when a transaction with a debit or credit card is processed.

-Finance Charges  are fees that a financial institution charges for borrowing money like closing costs and interests.

-Down Payment is a payment made at the beginning when purchasing something on credit.

According to this, the answer is that the option that includes the interest you will have to pay to a lender beyond the amount you need to purchase the car is finance charges.

A car can travel 480 miles on a full tank of petrol. The tank holds 60 litres. A driver fills the tank and sets off on a journey.How many litres of petrol will be left when the car has travelled 360 miles?

without calculator

Answers

Answer:

After travelling 360 miles, 15 litres of petrol will be left.

Step-by-step explanation:

If a car can travel 480 miles with a full tank of 60 liters of petrol, it could be said that each liter of petrol allows to travel 8 miles (480/60 = 8). Therefore, since the driver has driven his car for 360 miles, his tank has spent 45 liters of petrol (360/8 = 45). In conclusion, given that the tank has a capacity of 60 liters and that it was full at the time of departure, having spent 45 liters, 15 liters remain in the tank.

Estimate the sum of 17.36 and 8.7 BY ROUNDNG TO THR NEAREST WHOLE NUMBER BEFORE ADDING...?

A.9

B.10

C.25

D.26

E. None correct

Answers

Answer:

D. 26

Step-by-step explanation:

We have to round to whole numbers before adding.

When approximating to whole numbers, if the number after the decimal is less than 5, you round down to 0 but if it is greater or equal to 5, you round up to 1.

17.36 ≅ 17

8.7 ≅ 9

Therefore:

17 + 9 = 26

Each big square below represents one hole what percent is represented by the shaded area

Answers

Answer:

  145%

Step-by-step explanation:

There are 100 small squares in each large square. Since 100% is one whole, each small square represents 1%.

Count the shaded small squares. The process is made easier by the fact that there are 10 in a row.

145 small squares are shaded, so the percentage represented is ...

  145%

(1 point) The volume of the solid obtained by rotating the region enclosed by x=2y,y3=x(with y≥0) about the y-axis can be computed using the method of disks or washers via an integral V=∫ba ? with limits of integration a= and b= . The volume is V= cubic units. Note: You can earn full credit if the last question is correct and all other questions are either blank or correct.

Answers

[tex]x=2y[/tex] and [tex]x=y^3[/tex] intersect when

[tex]2y=y^3\implies y^3-2y=y(y^2-2)=y(y-\sqrt2)(y+\sqrt2)=0[/tex]

[tex]\implies y=0\text{ or }y=\sqrt2\text{ or }y=-\sqrt2[/tex]

We omit the negative root, since we only care for [tex]y\ge0[/tex].

In the interval (0, √2), we have [tex]y^3<2y[/tex]. Then the volume is given by the integral

[tex]\displaystyle\pi\int_0^{\sqrt2}(2y)^2-(y^3)^2\,\mathrm dy=\pi\int_0^{\sqrt2}4y^2-y^6\,\mathrm dy[/tex]

and so the volume is (32√2)/21 π.

What is the speed that a car reaches in m/s, if it travels 956km in 56sec?Help me!! MRU (Uniform Rectilinear Movement)

Answers

Answer:

17.07m/s

Step-by-step explanation:

v=d/t

d=956km

t=56sec

v=956/56

v=17.07m/s

lot showing the weights of puppiespuppies at the shelter where hehe volunteers. HeHe said that since 1 and one half1
1
2plus+22plus+2 and one fourth2
1
4plus+2 and three fourths2
3
4equals=8 and one half8
1
2​, the total weight of the puppiespuppies is 8 and one half8
1
2 lot showing the weights of puppiespuppies at the shelter where hehe volunteers. HeHe said that since 1 and one half1
1
2plus+22plus+2 and one fourth2
1
4plus+2 and three fourths2
3
4equals=8 and one half8
1
2​, the total weight of the puppiespuppies is 8 and one half8
1
2 poundspounds. Use the line plot to answer 4dash–7.

Answers

Answer:

dont know need points sorry

Step-by-step explanation:

Answer:

I'm confused on what to answer in this. Edit the question and put the question in it and then I will be able to answer it

Differentiate the function:
y=x^3+2x-1

Answers

Answer:

y' = 3x² + 2

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to Right

Algebra I

FunctionsFunction Notation

Calculus

Derivatives

Derivative Notation

Basic Power Rule:

f(x) = cxⁿ f’(x) = c·nxⁿ⁻¹

Step-by-step explanation:

Step 1: Define

Identify

y = x³ + 2x - 1

Step 2: Differentiate

Basic Power Rule:                                                                                             y' = 3x³⁻¹ + 1 · 2x¹⁻¹ - 0Simplify:                                                                                                              y' = 3x² + 2

Topic: AP Calculus AB/BC (Calculus I/I + II)

Unit: Derivatives

Book: College Calculus 10e

Joanie has $14. Then she got $23 for her birthday. Later she spend $5 on a book. Which number sentence can be used to find m, the amount of money Joanie has now?

A.
14+23-5=m

B.
14+23+5=m

C.
23-14+5=m

D.
23-14-5=m

Answers

Answer A

Step-by-step explanation:14+23-5

The quality control manager at a light bulb factory needs to estimate the mean life of a batch (population) of light bulbs. We assume that the population standard deviation is 100 hours. A random sample of 64 light bulbs from the batch yields a sample mean of 350. a) Construct a 95% confidence interval for the population mean of light bulbs in this batch. b) Do you think that the manufacturer has the right to state that the average life of the light bulbs is 400 hours

Answers

Answer:

a)95%  confidence intervals for the population mean of light bulbs in this batch

(325.5 ,374.5)

b)

The calculated value Z = 4 > 1.96 at 0.05 level of significance

Null hypothesis is rejected

The manufacturer has not right to take the average life of the light bulbs is 400 hours.

Step-by-step explanation:

Given sample size n = 64

Given  mean of the sample x⁻ = 350

Standard deviation of the Population σ = 100 hours

The tabulated value Z₀.₉₅ = 1.96

95%  confidence intervals for the population mean of light bulbs in this batch

[tex](x^{-} - Z_{\frac{\alpha }{2} } \frac{S.D}{\sqrt{n} } , x^{-} + Z_{\frac{\alpha }{2} }\frac{S.D}{\sqrt{n} } )[/tex]

[tex](350 - 1.96\frac{100}{\sqrt{64} } , 350 + 1.96\frac{100}{\sqrt{64} } )[/tex]

[tex](350 -24.5, 350 +24.5)[/tex]

(325.5 ,374.5)

b)

Explanation:-

Given mean of the Population μ = 400

Given sample size n = 64

Given  mean of the sample x⁻ = 350

Standard deviation of the Population σ = 100 hours

Null hypothesis : H₀:The manufacturer has right to take the average life of the light bulbs is 400 hours.

μ = 400

Alternative Hypothesis: H₁: μ ≠400

The test statistic

[tex]Z = \frac{x^{-}-mean }{\frac{S.D}{\sqrt{n} } }[/tex]

[tex]Z = \frac{350 -400}{\frac{100}{\sqrt{64} } }[/tex]

|Z| = |-4|

The tabulated value   Z₀.₉₅ = 1.96

The calculated value Z = 4 > 1.96 at 0.05 level of significance

Null hypothesis is rejected.

Conclusion:-

The manufacturer has not right to take the average life of the light bulbs is 400 hours.

j+ 12 =25 find the solution to equation algebtaically​

Answers

Answer:

j= 13

just subtract 12 from 25

Start by isolating the j.

Subtract 12 from both sides.

On the left, the 12 and -12 cancel.

On the right, 25 - 12 is 13.

So we have j = 13.

What is the probability of flipping a coin three times and getting either all heads or all tails?

Answers

Answer:

12.5 %

Step-by-step explanation:

Each time you probability of flipping one side is 50%, so when you do this three times (I think of x^3), your probability is going to be 0.5 * 0.5 * 0.5, or 12.5%

There are 14math teachers and 26 science teachers at school today. What is the ratio of math teachers to math and science teachers at school?

Answers

Answer is 7:20

It's basically asking "what is the ratio of math teachers to total teachers?" assuming there are only math and science teachers at this school. For the sake of simplicity, let's just go with that. We have 14 math teachers and 14+26 = 40 teachers total. The ratio of math to total is 14:40 which reduces to 7:20 when we divide both parts of the ratio by the GCF 2.

Answer: 7: 13

The ratio would be 14: 26, however you are most likely asked to simplify it. Which is why the answer would be 7: 13

I hope this helped! :DD

Parallel lines r and s are cut by two transversals, parallel lines t and u. Lines r and s are crossed by lines t and u to form 16 angles. Clockwise from top left, at the intersection of r and t, the angles are 1, 2, 3, 4; at the intersection of s and t, 5, 6, 7, 8; at the intersection of u and s, 9, 10, 11, 12; at the intersection of u and r, 13, 14, 15, 16. Which angles are corresponding angles with angle 8? Angle4 and Angle12 Angle2 and Angle10 Angle6 and Angle14 Angle3 and Angle9

Answers

Answer:

Angle 6 and Angle 13

Step-by-step explanation:

Because they are both parallel.

And they intersect at a given line.

Also cut by two transversals.

The angles that are corresponding angles with angle 8 are; Angles 6 and 14

How to find corresponding angles?

Corresponding angles are defined as the angles that are formed when two parallel lines are intersected by the transversal. This means that they are on the same side of the transverse line.

Now, from the given description and from the image of the line diagram shown in the brainly link attached, we can say that the angles that are corresponding to angle 8 are;

angles 6, 14, 16.

Thus, we conclude by saying that looking at the options, the ones that correspond to angle 8 are angle 6 and angle 14.

Read more about Corresponding angles at; https://brainly.com/question/20907188

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The vertex of the graph of f(x) = (x - 3| + 6 is located at

Answers

Answer:

The answer is The vertex of the graph of f(x) = |x – 3| + 6 is located at (3,6)

3

and

6

Step-by-step explanation:

Vertex of graph located at (3,6)

What is vertex?

A mathematical object's vertex is a special point where two or more lines or edges typically meet. Angles, polygons, and graphs are the most common examples of vertices.

Given equation f(x) = |x - 3| +6

after simplifying there will be two equations they are

y = x - 3 + 6 = x +3...….(1)

and y = -(x-3) +6

y = 9 - x...…(2)      

substitute value of equation 2 in eq. 1

9 - x = x + 3

      x = 3 and

substitute value of x in eq. 1

y = x + 3 =3 + 3

y = 6

x = 3, y = 6

Hence the intersecting points of both equation are (3,6)

Learn more about vertex

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What is the length of AC? PLEASE HELP ASAP WILL GIVE BRAINLIEST TY

Answers

Answer:

2.33 units

Step-by-step explanation:

[tex]\tan 25\degree =\frac{AC}{5}\\\\0.46630 = \frac{AC}{5}\\\\AC = 0.46630 \times 5\\AC =2.3315\\AC = 2.33 \: units[/tex]

A thermometer shows a temperature of Negative 20 and three-fourths degrees. A chemist recorded this temperature in her notebook using a decimal. Which number did the chemist write in the notebook?

-21.4 repeating
-21.3 repeating
-20.75
-20.34

Answers

Answer:

3rd option im positive

Step-by-step explanation:

Answer:

C

Step-by-step explanation:

I took the test

g(t) = 6t - 1

g ( ) = -7

Answers

Answer:

  g(-1) = -7

Step-by-step explanation:

Put the given value for g(t) into the first equation and solve for t.

  -7 = 6t -1

  -6 = 6t . . . . . . add 1

  -1 = t . . . . . . . . divide by 6

g(-1) = -7

Answer: -1

Step-by-step explanation:

If f(x) and f-1 (x)
are inverse functions of each other and f(x) = 2x+5, what is f-1 (8)?​

Answers

Answer:

For this case we have the following function:

 f (x) = 2x + 5

 Clearing x we have:

 2x = y - 5

 x = (y-5) / 2

 Rewriting:

 f (x) ^ - 1 = (x-5) / 2

 Evaluating x = 8:

 f (8) ^ - 1 = (8-5) / 2

 f (8) ^ - 1 = 3/2

 Answer:

 f (8) ^ - 1 = 3/2

 option 2

Answer:

3/2 B

Step-by-step explanation:

Edge

The measure of an angle is 75°. What is the measure of its supplementary angle?

Answers

Answer:

105

Step-by-step explanation:

Supplementary angles add to 180 degrees

Let the unknown angle be x

75+x = 180

Subtract 75 from each side

75+x-75=180-75

x  = 105

Find cos theta, tan theta, and csc theta, where is the angle shown in the figure.
Give exact values, not decimal approximations.

Answers

Remember (Soh) (Cah) (Toa). CSC is just the inverse of sine.

The exact values of [tex]cos\theta[/tex], [tex]tan\theta[/tex], and [tex]cosec\theta[/tex] are [tex]\frac{\sqrt{33} }{7}[/tex], [tex]\frac{4}{\sqrt{33} }[/tex] and [tex]\frac{7}{4}[/tex] respectively.

What is sine of an angle?

The sine (sin) of an acute angle in a right angled triangle is the ratio between the side opposite the angle and the hypotenuse of the triangle.

What is cosine of an angle?

In a right triangle, the cosine of an angle is the length of the adjacent side (A) divided by the length of the hypotenuse (H).

What is tangent of an angle?

The tangent of an angle is the ratio of the length of the opposite side to the length of the adjacent side.

What is cosecant of an angle?

In a right angled triangle, the cosecant of an angle is the length of the hypotenuse divided by the length of the side opposite the angle.

According to the given question.

We have a right angle triangle ABC.

In which

AB = 7

AC = 4

Now by Pythagoras Theorem

[tex]AB^{2} =AC^{2} +BC^{2}[/tex]

⇒ [tex](7)^{2} = (4)^{2} + BC^{2}[/tex]

⇒ [tex]49 = 16 +(BC)^{2}[/tex]

⇒ [tex]49 - 16=BC^{2}[/tex]

⇒ [tex]BC^{2} = 33[/tex]

⇒ [tex]BC=\sqrt{33}[/tex]

In the right angle triangle

Hypotenuse, AC = 7

The side BC is the adjacent side w.r.t angle θ.

And, Side BC is the opposite side w.r.t angle θ.

Therefore,

[tex]tan\theta=\frac{4 }{\sqrt{33} }[/tex]

[tex]cos\theta= \frac{\sqrt{33} }{7}[/tex]

[tex]sin\theta= \frac{4}{7}[/tex]

[tex]cosec\theta=\frac{1}{sin\theta} =\frac{1}{\frac{4}{7} } =\frac{7}{4}[/tex]

Hence, the exact values of [tex]cos\theta[/tex], [tex]tan\theta[/tex], and [tex]cosec\theta[/tex] are [tex]\frac{\sqrt{33} }{7}[/tex], [tex]\frac{4}{\sqrt{33} }[/tex] and [tex]\frac{7}{4}[/tex] respectively.

Find out more information about cosine, tangent and cosecant of an angle here:

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If y= 1/4x and x = -12, find y.

Answers

Answer:

y = -3

Step-by-step explanation:

y= 1/4x and x = -12

Substitute x=12 into the first equation

y = 1/4(-12)

y = -3

Answer:

-3

Step-by-step explanation:

1/4 x -12

A parallelogram piece of paper 40cm by 25cm is cut into small parallelogram 8cm by5cm . How many pieces can be obtained. Step by step please

Answers

step 1- multiply 40 by 25 to get 1000
step2- multiply 8 by 5 to get 40
step3- divide 1000 by 4 to get 250
answer. 250 pieces

Make h the subject of the relation V=1/3πr²h

Answers

Answer:h=3V/πr^2

Step-by-step explanation:

V=1/3πr^2h

Cross multiply

3V=πr^2h

Divide both sides by πr^2

3V/πr^2=πr^2h/πr^2

3V/πr^2=h

h=3V/πr^2

GUYS I NEED HELP ASAP



A rectangular playground is 40 feet wide. Find the area of this playground, if the fence around it, including the gates, is 200 feet long.

Answers

Answer:

[tex]A=2400ft[/tex]

Step-by-step explanation:

A rectangle is a closed planer quadrilateral with four  right angles and its opposite sides are the same length. The fence around it including the gates is 200 feet long, so basically they are providing the perimeter of the rectangle. The perimeter of a rectangle is equal to the sum of all its sides. Hence:

[tex]Perimeter=w+h+w+h=2w+2h\\\\Where:\\\\w=Width\\h=Height[/tex]

The ectangular playground is 40 feet wide, so:

[tex]w=40ft[/tex]

Therefore:

[tex]Perimeter=2w+2h\\\\200=2(40)+2h\\\\200=80+2h[/tex]

Solving for h:

[tex]2h=200-80\\\\2h=120\\\\h=\frac{120}{2} \\\\h=60ft[/tex]

The area of a rectangle is equal to the product of two of its contiguous sides, hence:

[tex]A=wh\\\\A=(40)(60)=2400ft[/tex]

I attached you a picture of the rectangle

Max wants to purchase a wall hanging. He is choosing between one shaped like a trapezoid and one shaped like a kite. He will choose the wall hanging with the greater area. Which wall hanging will Max choose?

Answers

Answer:

Max will choose the wall hanging that is shaped like a trapezoid.

Step-by-step explanation:

To find the area of the trapezoid, break it into a triangle and another trapezoid. Use the formula for the area of a triangle (A=base*height*1/2) and the formula for the area of a trapezoid (A=base+base*height*1/2). The area of the trapezoid is 672 square centimeters.

To find the area of the kite, break it into two identical triangles. (There's a horizontal line between them.) Use the formula for the area of a triangle for both, then add the two areas. The area of the kite is 648 square centimeters.

Finally, we know that 672>648. Therefore, Max will choose the wall hanging that is shaped like a trapezoid.

Hope this helps! Tell me if you have any other questions:)

Answer:trapezoid

Step-by-step explanation:

Plz help
What does “|” mean in mathematical term
Thanks

Answers

Answer:

Step-by-step explanation:

If you meant " | ", as in |x|, that's "absolute value."  The domain of this function is "all real numbers," and the range is "all real numbers zero or greater."

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