Score for Question 3: of 5 points)
. What is the area of triangle BCD to the nearest tenth of a square centimeter? Use special right triangles to
help find the height. Show your work.

Score For Question 3: Of 5 Points). What Is The Area Of Triangle BCD To The Nearest Tenth Of A Square

Answers

Answer 1

Answer:

[tex] \frac{25 \sqrt{3} }{2} [/tex]

Step-by-step explanation:

Height = 5 * tan 60°

[tex]height \: = 5 \sqrt{3} [/tex]

[tex]area = \frac{1}{2} \times 5 \times 5 \sqrt{3 } = \frac{25 \sqrt{3} }{2} [/tex]


Related Questions

A car is averaging 50 miles per hour. If the car maintains this speed, how many minutes less would a 450-mile trip take than a 475-mile trip?

Answers

Answer:

1/2 a minute (30 seconds)

Step-by-step explanation:

475/50=9.5

450/50=9

9-9.5=.5

prove that (3-4sin^2)(1-3tan^2)=(3-tan^2)(4cos^2-3)

Answers

Answer:

Proof in the explanation.

Step-by-step explanation:

I expanded both sides as a first step. (You may use foil here if you wish and if you use that term.)

This means we want to show the following:

[tex]3-9\tan^2(\theta)-4\sin^2(\theta)+12\sin^2(\theta)\tan^2(\theta)[/tex]

[tex]=12\cos^2(\theta)-9-4\cos^2(\theta)\tan^2(\theta)+3\tan^2(\theta)[/tex].

After this I played with only the left hand side to get it to match the right hand side.

One of the first things I notice we had sine squared's on left side and no sine squared's on the other. I wanted this out. I see there were cosine squared's on the right. Thus, I began with Pythagorean Theorem here.

[tex]3-9\tan^2(\theta)-4\sin^2(\theta)+12\sin^2(\theta)\tan^2(\theta)[/tex]

[tex]3-9\tan^2(\theta)-4(1-\cos^2(\theta))+12\sin^2(\theta)\tan^2(\theta)[tex]

Distribute:

[tex]3-9\tan^2(\theta)-4+4\cos^2(\theta)+12\sin^2(\theta)\tan^2(\theta)[/tex]

Combine like terms and reorder left side to organize it based on right side:

[tex]4\cos^2(\theta)-1+12\sin^2(\theta)\tan^2(\theta)-9\tan^2(\theta)[/tex]

After doing this, I since that on the left we had products of sine squared and tangent squared but on the right we had products of cosine squared and tangent squared. This problem could easily be fixed with Pythagorean Theorem again.

[tex]4\cos^2(\theta)-1+12\sin^2(\theta)\tan^2(\theta)-9\tan^2(\theta)[/tex]

[tex]4\cos^2(\theta)-1+12(1-\cos^2(\theta))\tan^2(\theta)-9\tan^2(\theta)[/tex]

Distribute:

[tex]4\cos^2(\theta)-1+12\tan^2(\theta)-12\cos^2(\theta)\tan^2(\theta)-9\tan^2(\theta)[/tex]

Combined like terms while keeping the same organization as the right:

[tex]4\cos^2(\theta)-1+3\tan^2(\theta)-12\cos^2(\theta)\tan^2(\theta)-9\tan^2(\theta)[/tex]

We do not have the same amount of the mentioned products in the previous step on both sides. So I rewrote this term as a sum. I did this as follows:

[tex]4\cos^2(\theta)-1+3\tan^2(\theta)-12\cos^2(\theta)\tan^2(\theta)-9\tan^2(\theta)[/tex]

[tex]4\cos^2(\theta)-1+3\tan^2(\theta)-4\cos^2(\theta)\tan^2(\theta)-8\cos^2(\theta)\tan^2(\theta)-9\tan^2(\theta)[/tex]

Here, I decide to use the following identity [tex]\cos\theta)\tan(\theta)=\sin(\theta)[/tex]. The reason for this is because I certainly didn't need those extra products of cosine squared and tangent squared as I didn't have them on the right side.

[tex]4\cos^2(\theta)-1+3\tan^2(\theta)-4\cos^2(\theta)\tan^2(\theta)-8\cos^2(\theta)\tan^2(\theta)-9\tan^2(\theta)[/tex]

[tex]4\cos^2(\theta)-1+3\tan^2(\theta)-4\cos^2(\theta)\tan^2(\theta)-8\sin^2(\theta)-9\tan^2(\theta)[/tex]

We are again back at having sine squared's on this side and only cosine squared's on the other. We will use Pythagorean Theorem again here.

[tex]4\cos^2(\theta)-1+3\tan^2(\theta)-4\cos^2(\theta)\tan^2(\theta)-8\sin^2(\theta)-9\tan^2(\theta)[/tex]

[tex]4\cos^2(\theta)-1+3\tan^2(\theta)-4\cos^2(\theta)\tan^2(\theta)-8(1-\cos^2(\theta))-9\tan^2(\theta)[/tex]

Distribute:

[tex]4\cos^2(\theta)-1+3\tan^2(\theta)-4\cos^2(\theta)\tan^2(\theta)-8+8\cos^2(\theta)-9\tan^2(\theta)[/tex]

Combine like terms:

[tex]12\cos^2(\theta)-9+3tan^2(\theta)-4\cos^2(\theta)\tan^2(\theta)[/tex]

Reorder again to fit right side:

[tex]12\cos^2(\theta)-9+4\cos^2(\theta)\tan(\theta)+3\tan^2(\theta)[/tex]

This does match the other side.

The proof is done.

Note: Reordering was done by commutative property.

**Yoxelt buys 4 1/ 2 gallons of soda. One-fourth of the soda he bought was Pepsi and the rest was Sprite. How many gallons of Pepsi did Yoxelt buy? Show all work below.

Answers

Answer:

1 1/8

Step-by-step explanation:

1/4 of 4 1/2 is Pepsi.

1/4 * 4 1/2 = (1/4) * 4 + (1/4) * (1/2) = 1 1/8

Barry has been watching the geese that live in his neighborhood. The number of geese changes each week. n f(n) 1 56 2 28 3 14 4 7 Which function best shows the relationship between n and f(n)? f(n) = 28(0.5)n f(n) = 56(0.5)n−1 f(n) = 56(0.5)n f(n) = 112(0.5)n−1

Answers

Answer:

B. f(n) = 56(0.5)^n-1

Step-by-step explanation:

 First, You have to find out the starting population, if you look at the problem you see the population starts at 56

f(x) = 56

Second, you know that the population goes down 50% each week so it has a decay of 0.5

f(x) = 56(0.5)

 Third,  you need to add the exponent of n to make it exponential.  But, if you just add n then the the population would be 28 on week 1 which is incorrect. To fix that you make the exponent n-1 so when you are on week 1 it doesn't become 28 but it stays on 56, and on week 2 it's 28, ect

f(x) = 56(0.5)^n-1

help..? why are there so many parentheses..?can you plz give a step by step on how to slove the equation?

Answers

Answer:

= -11

Step-by-step explanation:

-(-(11-22))

= -(-11+22)

= 11 - 22

= -11

Simplify the expression. (3x2 – 4x + 1) + (-x2 + x – 9)

Answers

[tex](3x^2 - 4x + 1) + (-x^2 + x - 9)=\\3x^2-4x+1-x^2+x-9=\\2x^2-3x-8[/tex]

= (6x+4x+1)+(-2x+x-9)
= (2x+1)+(-x-9)
= 2x+1-x-9
= x-8

Find the vertex and the length of the latus rectum. x= 1/2 (y - 5)² + 7

Answers

Answer:

Vertex = (7,5)

Length of latus rectum = 2 units

Step-by-step explanation:

The vertex form of a parabola is

[tex]x=a(y-k)^2+h[/tex]    ...(1)

where, (h,k) is vertex and length of latus rectum is [tex]\left|\dfrac{1}{a}\right|[/tex].

The given equation is  

[tex]x=\dfrac{1}{2}(y-5)^2+7[/tex]    ...(2)

On comparing (1) and (2), we get

[tex]h=7,k=5,a=\dfrac{1}{2}[/tex]

So, vertex of parabola is (7,5).

Length of latus rectum is

[tex]L.R.=\left|\dfrac{1}{a}\right|=\left|\dfrac{1}{\frac{1}{2}}\right|=2[/tex]

Therefore, the length of the latus rectum is 2 units.

A pet store has m tanks of fish. Each tank has 35 fish. Using m, write an expression for the total number of fish in the store

Answers

Answer:

35m

Step-by-step explanation:

Each tank has 35 fish and the total fish tanks is m, so to find the total you will need to do 35*m.

This is an expression because it does not have anything it is equal to.

Expression: No equal sign

Equation:Equal Sign

Hope this helps!:)

What is negative 14 minus 5

Answers

Answer:

-19

Step-by-step explanation:

(-14)

-5

-------

14+5=19

add the negative

-19

For the function F(x)= 1/x-2 whose graph is shown below, what is the relative value of F(x) when the value of x is close to 2?​

Answers

Answer:

10,000

Step-by-step explanation:

Find the solution for this system of equations. 2x - 3y = 2 x= 6y -5

Answers

Answer:

Step-by-step explanation:

2(6y - 5) = 2

12y - 10 = 2

12y = 12

y = 1

x = 6(1) - 5

x = 6 - 5 = 1

(1,1)

Answer: (1,1)

Step-by-step explanation: 2(6y - 5) = 2

12y - 10 = 2

12y = 12

y = 1

x = 6(1) - 5

x = 6 - 5 = 1

(1,1)

PLEASE HELPP on THIS PICTURE FOR ONE OF MY QUESTIONS

Answers

Answer:

Linear pair postulate

Step-by-step explanation:

The Linear Pair Postulate states: "If two angles form a linear pair, then the angles are supplementary; that is, the sum of their measures is 180 degrees

A linear pair of angles is such that the sum of angles is 180 degrees.

kelly used 2.1 x 10^6 KB of data so far this month. her younger brother joseph used 7 x 10^5 KB of the data so far this month if their share family plan allows them to use 3,000,000 KB of the data each month, how much data usage o they have available for the remainder of this month?

Answers

Answer:

They will 200,000 kb left

Step-by-step explanation:

  2.1 x 10^6=2,100,000     7 x 10^5=700,000

What is the length of LM? (Question and answer choices provided in picture.)

Answers

Answer:

24√3

Step-by-step explanation:

cos∅ = adjacent over hypotenuse

Step 1: Use cos∅

cos30° = LM/48

Step 2: Multiply both sides by 48

48cos30° = LM

Step 3: Evaluate

LM = 24√3

Answer:

[tex]\large \boxed{24 \sqrt{3} }[/tex]

Step-by-step explanation:

The triangles are right triangles. We can use trig functions to solve.

cos θ  = adj/hyp

Take the triangle KLM.

cos 30 = LM/KL

cos 30 = LM/48

Multipy both sides by 48

(48) cos 30 = LM/48 (48)

Simplify.

48 cos30 = LM

24√3 = LM

Escreva expressões algébricas mais simples e equivalentes às expressões abaixo.

Answers

Answer:

Step-by-step explanation:

(4a+8)/2 = 4a/2  + 8/2 = 2a + 4(5x + 6x + 22)/11 = (11x+22)/11 = 11x/11 + 22/11 = x + 2{6(x+2)-12}/3 = {6x+12 - 12}/3 = 6x/3 = 2x(

area of a parrollelogram with a base length of 2.9ft and a height of 5.5ft​

Answers

Answer:

[tex] \boxed{15.95 \: {ft}^{2} }[/tex]

Step-by-step explanation:

base length ( b ) = 2.9 ft

Height ( h ) = 5.5 ft

Let's find the area of parallelogram:

Area of parallelogram : [tex] \mathsf{ = b \times h}[/tex]

plug the values

⇒[tex] \mathsf{2.9 \times 5.5}[/tex]

Multiply

⇒[tex] \mathsf{15.95}[/tex] ft²

--------------------------------------------------------------------

Extra information:

Parallelogram

The quadrilateral in which opposites sides are parallel is called a parallelogram.

The opposite sides of a parallelogram are equal.The opposite angles of a parallelogram are equal.The diagonals of a parallelogram bisect each other.The area of a parallelogram = base × height

Hope I helped!

Best regards!

Area of Parallelogram formula = LxW or LxH. L(2.9) x H(5.5) = 15.95 ft. Hope this helps!

What is the value of z for the equation fraction 1 over 2z = −fraction 3 over 4 + fraction 1 over 4z? −3 −1 1 3

Answers

Answer:

z= -3

Step-by-step explanation:

Given:

1/2z =-3/4 + 1/4z

Collect like terms

1/2z - 1/4z = -3/4

Add 1/2z - 1/4z

2z-z / 4 = -3/4

We have

z/4=-3/4

Same as

z(1/4) = -3/4

Divide both sides by 1/4

z(1/4) ÷ 1/4 = -3/4÷1/4

z(1/4) × 4/1= -3/4 × 4/1

z(4/4) = -12/4

z= -3

The value of z= -3

Answer:

-3

Step-by-step explanation:

I got it right on the test

Point E is on line segment DF. Given DE=9 and DF=11, determine the length EF.

Answers

Answer: Line EF=2

Step-by-step explanation: 11 minus 9 is equal to 2. So line EF is equal to 2.

Marta esta poniendo sus libros en una estantería. Le faltan 7 libros para poder poner 12 en cada estante; sin embargo, si pone 10 libros en cada estante, se quedan 5 libros sin poner. ¿Cuantos es antes tiene la estantería?

Answers

Answer:

x = 6       la cantidad de estantes

y = 65    cantidad de libros

Step-by-step explanation:

LLamemos "x" la cantidad de estantes que tiene Marta, y llamaremos "y" la cantidad de libros.

La primera condición que se debe cumplir es que cuando Marta coloca 12 libros en cada estante entonces le faltan 7, esto lo expresamos así:

y  +  7  = 12*x        (1)

La segunda condición establece que si Marta coloca los libros en número de 10 por estante le quedan 5 sin colocar, luego esto en lenguaje matemático se expresa así:

y  -   5   = 10*x     (2)

Ahora hemos obtenido un sistema de dos ecuaciones con dos incógnitas que se resuelve por cualquiera de los métodos conocidos, usaremos el método de sustitución.

Despejamos   y en la primera ecuación y lo sustituimos en la segunda, de esa forma obtendremos el valor de x

y  =  12*x  - 7

(12*x - 7 ) - 5  = 10*x

2*x  -12 = 0

2*x = 12

x = 6       la cantidad de estantes, y

y  =  12*x -7

y  =  72  -  7

y =  65    cantidad de libros

10. RP3-M

Jeanette purchased a concert ticket on a web site. The original price of the ticket was $75.

She used a coupon code to receive a 20% discount. The website applied a 10% service fee

to the discounted price. Jeannette's ticket was less than the original price by what percent?

Answers

Answer:

Jeannette's ticket was less than the original pice by 30%

Step-by-step explanation:

original price = $75

percentage discount = 20% of original price = 20% of $75

discounted price = [tex]\frac{20}{100} \times\ 75\ =\ 15[/tex]

discounted price = $15

website service fee = 10% of original price

website service fee = [tex]\frac{10}{100}\times 75 = \$7.5[/tex]

New discounted price = discount price + website service fee

= 15 + 7.5 = $22.5

Next, let us calculate what percentage of the original price that will give the new discount price.

Let the percentage of the original price = x%

x% of 75 = $22.5

[tex]\frac{x}{100} \times\ 75\ = 22.5\\\\\frac{75x}{100} = 22.5\\\\75x = 2250\\\\x = \frac{2250}{75} \\\\x = 30[/tex]

Therefore, Jeannette's ticket was less than the original pice by 30%

solve for x 5(x+1)=4(x+8)

Answers

Answer:

x=27

Step-by-step explanation:

expanding the above expression we get

5x+5=4x+32

grouping numbers with coefficient of x at the left side and constant at the right side we get

5x-4x=32-5

x=27

To solve this equation, we start by distributing both the 5 and the 4 through both set of parentheses.

This gives us 5x + 5 = 4x + 32.

Now subtract 4x from both
sides to get x + 5 = 32.

Now subtract 5 from both sides and x = 27.

Lenny is competing with his cousin, Jasper, in an indoor rock-climbing contest. At the start of the climb, Lenny makes his way 5 ¼ feet up the wall, while Jasper climbs 9 ¾ feet. How much farther did Jasper climb than Lenny?

Answers

Answer:

[tex]4\frac{1}{2}[/tex] feet further.

Step-by-step explanation:

Since these are mixed numbers that are both in fourths, we can easily subtract the two numbers. However, I find it easier if we first convert both mixed numbers into improper fractions.

[tex]5\frac{1}{4} = \frac{5\cdot4+1}{4} = \frac{21}{4}[/tex]

[tex]9\frac{3}{4} = \frac{9\cdot4+3}{4} = \frac{39}{4}[/tex]

Now we can subtract the numerators:

[tex]\frac{39}{4} - \frac{21}{4} = \frac{39-21}{4} = \frac{18}{4}[/tex]

[tex]\frac{18}{4}[/tex] simplifies down to [tex]\frac{9}{2}[/tex].

Converting  [tex]\frac{9}{2}[/tex] to a mixed number is easy - 2 goes into 9 4 times (8) with one remainder so:

[tex]4\frac{1}{2}[/tex] .

Hope this helped!

There are a total of two hundred students and chaperones going on a
field trip. Each bus can hold 60 passengers. How many buses will be
used for the field trip? Explain why your answer is reasonable.

Answers

Answer:

4 bus is required for field trip to carry 200 passengers.

Step-by-step explanation:

Total no . of passengers = 200

let the be x bus required to carry 200 passengers

capacity of 1 bus = 60 passengers

capacity of x bus = 60*x passengers = 60x passengers

Thus,

60x = 200

x = 200/60 = 3 2/3

thus, 3.66 bus is required , but no. of bus cannot be in fraction hence we take integral value greater than 3.66 which is 4

Thus, 4 bus is required for field trip to carry 200 passenger.

Which expression is equivalent to (–2)(a + 6)?
A. –2a + 6
B. 2a + 12
C. –2a – 12
D. –2a + 12

Answers

The answer is option c.

what is the radical of 5√72 PLZ HELP!

Answers

Answer: Exact Form: 30√2

Decimal Form:42.42640687…

Step-by-step explanation: Simplify the radical by breaking the radicand up into a product of known factors, assuming positive real numbers.

I hope this helped :)

Answer:

  30√2

Step-by-step explanation:

The radical portion of the given expression is √72.

__

Perhaps you want the simplest form of your expression. Factor out the perfect squares from under the radical.

  [tex]5\sqrt{72}=5\sqrt{36}\sqrt{2}=5\cdot 6\sqrt{2}=\boxed{30\sqrt{2}}[/tex]

BRAINLIEST, 5 STARS AND THANKS IF ANSWERED CORRECTLY.

A quadratic equation with a negative discriminant has a graph that..

A. touches the x-axis but does not cross it
B. opens downward and crosses the x-axis twice
C. crosses the x-axis twice.
D. never crosses the x-axis.

Answers

Answer:

never crosses the x-axis.

Step-by-step explanation:

     A quadratic equation with a negative discriminant has a graph that - never crosses the x-axis.

Answer:

The graph of a quadratic equation that has a negative discriminant is the one that never intersect x-axis. The graph of a quadratic equation that has a zero discriminant is the one that intersect x-axis at only one point. To be clearer, it can be seen in the attached image.

Step-by-step explanation:

Answer D

Here's a graph of a linear function. Write the
equation that describes that function.
Express it in slope-intercept form.

Answers

there is no visible graph

Step-by-step explanation:

Is there any video related to this or can you explain how to do it

Answers

Angles ECD  and CEF add to 180

40+140 = 180

So that means we have EF parallel to CD (due to the same side interior angle theorem)

--------------

Angles BCE and ECD combine to 30+40 = 70, which is congruent to angle ABC = 70 as well.

In other words, this shows angle ABC = angle BCD. Both of these angles are alternate interior angles. Since they're congruent, they lead to AB being parallel to CD.

--------------

So far we have

AB || CD

CD || EF

Using the transitive property, we can then link the two statements to say AB || EF. Think of a chain where CD is the common link. We go from AB to CD, then from CD to EF. So we can just take a single path from AB to EF.

It's like saying "P --> Q and Q --> R, therefore P --> R"

HELP!!!
The solutions to (x + 3)^2- 4=0 are x = -1 and x = -5

True or false

Answers

Answer:

False

Step-by-step explanation:

We can simplify this equation and then solve for x.

[tex](x+3)^3-4=0\\\\x^2+6x+9-4=0\\\\x^2+6x+5=0\\\\(x+2)(x+3)=0\\\\x=-3\\x=-2[/tex]

As you can see, the solutions are not x=-1 and x=-5.

Therefore, the answer is false.

Answer:

True

Step-by-step explanation:

Given

(x + 3)² - 4 = 0 ( add 4 to both sides )

(x + 3)² = 4 ( take the square root of both sides )

x + 3 = ± [tex]\sqrt{4}[/tex] = ± 2 ( subtract 3 from both sides )

x = - 3 ± 2

Thus

x = - 3 - 2 = - 5

x = - 3 + 2 = - 1

the area of a trapezium is 14.7cmsquare. if the parallel sides are 5.3cm and 3.1cm long,find the perpendicular distance between them

Answers

The perpendicular distance of the trapezoid is 3.5 cm

How to determine the perpendicular distance?

The given parameters are:

Parallel sides = 5.3 cm and 3.1 cmArea = 14.7 square cm

The area of a trapezoid is:

Area = 0.5 * (Sum of parallel sides) * perpendicular distance

So, we have:

14.7 = 0.5 *(5.3 + 3.1) * perpendicular distance

Evaluate

Perpendicular distance = 3.5

Hence, the perpendicular distance of the trapezoid is 3.5 cm

Read more about area at:

https://brainly.com/question/76387

#SPJ1

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