f(x)=2x^2 find f(-3)

Answer:

[tex]gradient = - 3 \\ y = mx + c \\ 2 = ( - 3 \times 0) + c \\ c = 2 \\ \therefore \: y = - 3x + 2 \\ y = 2 - 3x[/tex]

Answer:

{x,y}={5,-3}

Step-by-step explanation:

Answer:

7√3

Step-by-step explanation:

tan 60° = x/7

√3 = x/7

x = 7√3

Answer:

y-1 = 2(x+2)

Step-by-step explanation:

Point slope form of a line is

y-y1 = m(x-x1) where m is the slope and (x1,y1) is a point on the line

y -1 = 2(x - -2)

y-1 = 2(x+2)

Complete question:

Points A, B, and C are midpoints of the sides of right triangle DEF. Triangle A B C is inside triangle D E F. Point A is the midpoint of side F D, point B is the midpoint of side D E, point C is the midpoint of side F E. Angles D F E and A B C are right angles. The length of D E is 10 centimeters, the length of F D is 6 centimeters, and the length of F E is 8 centimeters. Which statements are true? Select three options. (The formula for the area of a triangle is A = One-halfbh.)

Answer:  

2. A-C = 5 cm

3. B-A = 4 cm

4. The perimeter of triangle A-B-C = 12 cm.

Step-by-step explanation:

First, picture a triangle formed by points D-E-F.

Now,

These values suggest that

The perimeter of the interior triangle ABC = 3cm + 5cm + 4cm = 12 cm

The total area of the interior triangle ABC is 1/4 the area of triangle DEF. You can see in the picture that there are four equal triangles inside DEF.

Answer:

B C and D

Step-by-step explanation:

right on edge

Answer:

all real values of x where 1 < x < 4

If there is anything you don't understand let me know.  Also, since the graph is supposedly shown you may even be able to get the information just by looking at the graph.  

Step-by-step explanation:

A graph  goes from being negative to positive (or the other way around) by passing through the x axis.  Or in other words when f(x) = 0.  So the trick is to find all 0s and then test if it is poitive or negative before and after the 0.  

f(x) = (x+2)(x-4) is in factored form, so it gives the 0s.  in factored form the 0s are the negatives of the numbers int he parenthesis.  Or in other words (x+a)(x+b) would have 0s at -a and -b.  Notie it is x+a but the 0 is at -a.  so for (x+2)(x-4) the zeroes would be -2 and 4.

Then checking, we can say it is positive before -2, negative after -2 up until 4, then it is positive again.

For increasing and decreasing for anything other than a quadratic and linear function you need calculus.  Since this is a quadratic though you don't need it.

With quadratics you need to know they have two parts.  An increasing part and decreasing part.  If you draw the graph of x^2 you can see it decreases until (0,0) then it starts increasing.  -x^2 is the opposite.  it won't always have the same changing point, but you can always tell if it increases first or decreases first.  You look at if the coefficient next to x^2 is positive of negative.  

In (x+2)(x-4) We have to expand first.  so it becomes x^2 - 2x - 8.  x^2 has 1 as its coefficent so we know it decreases first then increases.  Also looking at (x+2)(x-4) you could say since the two xs have the same sign we also know it would be that.  is one was positive and one negative, like (2x+1)(-3x+1) we would be able to say it increases first then decreases.  

To know when it switches, since it is in factored form you find the point in the middle of the two zeroes, and that is where it switches.  Since the zeroes are -2 and 4 we can say the middle (called the vertex) is at x=1 since it is 3 away from both 0s.  So it decreases up until 1 then increases.  

The different forms of quadratics have different easy methods of finding the vertex.

We could also actually use this information to say, since it is decreasing first we know it is positive before the first 0, then negative until the second 0, then positive again.  Still would have to find the 0s though.

So now we know it is positive and decreasing until x=-2, negative and decreasing until 1, negative and increasing until 4, then increasing after that.

Since you want negative and increasing, that is 1 < x < 4

Answer:

75 %

Step-by-step explanation:

Answer:

21 cm²

Step-by-step explanation:

Applying,

A = (a+b)h/2............. Equation 1

Where A = area of the trapezium, a = length of the first parallel side, b = length of the second parallel side, h = height.

From the diagram

Given: a = 5 cm (5 grids), b = 9 cm (9 grids), h = 3 cm (3 grids)

Substitute these values into equation 1

A = 3(5+9)/2

A = 3(14)/2

A = 3×7

A = 21 cm²

Answer:

2015-2010=5

50÷5=10

120-50=70

2017-2015=2

2*10=20

70-20=50mg

2018=50mg

Answer 20%

Step-by-step explanation:

Answer:

58 degrees

Step-by-step explanation:

The middle line in the box is the meadian so it points to 58 so yeah! Hope this helps! Good Luck!

Answer:

64

Step-by-step explanation:

Answer

IS 2/4

Step-by-step explanation:

1/3 = 4/12  1/4 = 3/12  4/12+3/12= 6/12 = 2/4

Answer:

(3 , 0 )

Step-by-step explanation:

At x-axis, y-co ordinate is 0

So, (3,0)

Answer: (3, 0)

Step-by-step explanation: The x-intercept is a point where a line crosses the x-axis and it's important to understand that all x-intercepts have a y-coordinate of zero. So the point (3, 0)  is the x-axis.

In the picture below, I have plotted a few points including the point

in this problem to show you that all x-intercepts have a y-coordinate of zero.

Answer:

4 1250 m

Step-by-step explanation:

Hope it helps you.

Answer:

C

Step-by-step explanation:

Answer:

c

Step-by-step explanation:

it the only one that make sense

Answer:

second option : the side length was multiplied by 5.

Step-by-step explanation:

a = side length of the original square

A² = a×a

(a+5)×(a+5) = a² + 10a + 25

and that should be equal to a²×25

a² + 10a + 25 = 25a² ?

10a + 25 = 24a²

no, that is not true for all a

a×5 × a×5 = a²×25 = 25A²

this is the correct solution, as it is true for all a.

For the area to be  25a², the side length was increased by 5.

Let a be the side length of the original square, hence:

A = a²

Increasing the length by 5 will give:

(a+5)×(a+5) = a² + 10a + 25

Factorizing the result

a² + 10a + 25 = (a+5)²

a² + 10a + 25 = 25a²

This shows that for the area to be  25a², the side length was increased by 5.

Learn more on area of square here: https://brainly.com/question/25092270

Answer:

Hi, today we learned about (the lesson you choose)  and the teacher told me to tell you what to do so you need to do your work or you will get in trouble

Step-by-step explanation:

Answer:

Option B is correct

Step-by-step explanation:

Doug is x years old, so Byron is x+3 years old. The product of their ages would then be x times x+3:

x(x+3) = 40

x2 + 3x = 40

x2 + 3x + 40 = 0

Now, factor the equation:

(x+8)(x-5) = 0

Then, solve for both values of x:

x+8 = 0

x = -8

x-5 = 0

x = 5

As no one can have a negative age, we simply disregard x=-8 as invalid. Therefore, Doug is 5 years old & Byron must be 5+3 - or 8 years old.

Answer:

Doug is 10 years old; option A

Step-by-step explanation:

set up expressions using the information you already know:

B (byron)

D (doug)

B = D + 3

B * D = 40

you can now solve by plugging in an expression for the variable B in the second equation.  

D + 3 * D = 40

D + 3D = 40

(combine like terms)

4D = 40

(divide by 4 on both sides to isolate the variable and balance the equation)

4D/4 = 40/4

D = 10

So, the answer is A; Doug is 10 years old

Step-by-step explanation:

Let the increase in the size of the length and breath be 'x'.

The area of the rectangle = 12in × 8in

=96 in²

From the question,

(12+x)(8+x)=96×2 in²

or, 96+12x+8x+x²= 192

or, x²+20x+96-192=0

or, x²+20x-96=0

or, x²+24x-4x-96=0

or, x(x+24)-4(x+24)=0

or, (x-4)(x+24)=0

Either, Or,

x-4=0 x+24=0

Therefore, or, x= –24 (Which is impossible)

x=4

So the new dimensions are 12+4=16 inch and 8+4=12 inch.

Answer:

Angle A: 28 degrees

Angle B: 24 degrees

Step-by-step explanation:

Hi there!

The angle that measures 52 degrees (angle DCA) is one of the exterior angles of a triangle. An exterior angle of a triangle is equal to the sum of the opposite interior angles, which in this case would be angles A and B. Knowing this, we can set up the following equation:

[tex]4y-4+3y=52[/tex]

1) Solve for y

[tex]4y-4+3y=52[/tex]

Combine like terms

[tex]7y-4=52[/tex]

Add 4 to both sides to isolate 7y

[tex]7y-4+4=52+4\\7y=56[/tex]

Divide both sides by 7

[tex]\frac{7y}{7}=\frac{56}{7} \\y=8[/tex]

Therefore, y is equal to 8.

2) Solve for angles A and B

Angle A:

[tex]4y-4\\=4(8)-4\\=32-4\\=28[/tex]

Angle B:

[tex]3y\\=3(8)\\=24[/tex]

I hope this helps!

Answer:

Step-by-step explanation:

tan x = 5.6/9.7

tan x = 0.57732

x = 29.9 to nearest tenth

I hope I'm correct if not I tried my best

bye :-)

Answer:

221

Step-by-step explanation:

Substitute x = 7 and y = 8 into the expression

5(7)² - 3(8)

= 5(49) - 24

= 245 - 24

= 221

Answer:

P = 20 and A = 24

Step-by-step explanation:

6+6+4+4 = 20

6*4 = 24

Hope this helps

Answer:

$1.50

Step-by-step explanation:

25% of 6 is basically just 6/4, which is 1.5.

This is money we're talking about, so the answer is $1.50

Step-by-step explanation:A≈50.27km²

d Diameter  

8

km

d

r

r

r

d

d

C

A

Using the formulas

A=πr2

d=2r

Solving forA

A=1

4πd2=1

4·π·82≈50.26548km²

Questions and answers the answer is 50.27km

Answer:

-2/5

Step-by-step explanation:

( -8/ 125) ^ 1/3

We know (a/b) ^ 1/3 = a^ 1/3  / b^1/3

( -8) ^ 1/3  / ( 125) ^ 1/3

Rewriting

( -2^3) ^ 1/3  / ( 5^3) ^ 1/3

We know that a^b^c = a^(b*c)

-2^(3* 1/3)  / 5^(3 * 1/3)

-2 / 5

Answer:

-2/5

Step-by-step explanation: