Evaluate the following expression when x=3. 2x+7

stellarik [79]

Answer:

12m

Step-by-step explanation:

You can break this shape down into a square and a trapezoid. Frist you can find the area of the square by multiplying 2 by 5 to get 10. Then you would find the area of a trapezoid by doing Area = 1/2height(base1+base2). We can find the height by subtracting 5 from 9. (We do this because we know the side of the square is 5m) Therefore the height would be 4m. We know the bases are 2 and 4. From there you can plug those numbers in to the formula. Area=1/2 * 4 (2 + 4)

Area= 1/2 * 4 (6)

Area = 2(6)

Area = 12m

4 0

3 years ago

True or False: If circumference of a circle is 12*3.14, then its area is 36*3.14.

strojnjashka [21]

Answer: true

Step-by-step explanation:

8 0

3 years ago

This is distance & midpoint formulas I don’t know how to solve this can anyone help?

Tasya [4]

Answer:

midpoint formula: (x₁ + x₂)/2, (y₁ + y₂)/2

distance: √[(x₂ - x₁)² + (y₂ - y₁)²]

Step-by-step explanation:

What points are you trying to calculate the distance and the midpoint for?

8 0

2 years ago

The axis of symmetry for the function f(x) = –2x2 + 4x + 1 is the line x = 1. Where is the vertex of the function located?

egoroff_w [7]

Answer:

(1, 3)

Step-by-step explanation:

You are given the h coordinate of the vertex as 1, but in order to find the k coordinate, you have to complete the square on the parabola. The first few steps are as follows. Set the parabola equal to 0 so you can solve for the vertex. Separate the x terms from the constant by moving the constant to the other side of the equals sign. The coefficient HAS to be a +1 (ours is a -2 so we have to factor it out). Let's start there. The first 2 steps result in this polynomial:

$-2x^2+4x=-1$ . Now we factor out the -2:

$-2(x^2-2x)=-1$ . Now we complete the square. This process is to take half the linear term, square it, and add it to both sides. Our linear term is 2x. Half of 2 is 1, and 1 squared is 1. We add 1 into the set of parenthesis. But we actually added into the parenthesis is +1(-2). The -2 out front is a multiplier and we cannot ignore it. Adding in to both sides looks like this:

$-2(x^2-2x+1)=-1-2$ . Simplifying gives us this:

$-2(x^2-2x+1)=-3$

On the left we have created a perfect square binomial which reflects the h coordinate of the vertex. Stating this binomial and moving the -3 over by addition and setting the polynomial equal to y:

$-2(x-1)^2+3=y$

From this form,

$y=-a(x-h)^2+k$

you can determine the coordinates of the vertex to be (1, 3)

5 0

3 years ago

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Triangles DEF and D'E'F' are shown on the coordinate plane below: . . Triangle DEF and triangle D prime E prime F prime with ord

Brilliant_brown [7]

The correct answer is:
180° rotation.

Explanation: 
Comparing the points D, E and F to D', E' and F', we see that the x- and y-coordinates of each have been negated, but they are still in the same position in the ordered pair. 

A 90° rotation counterclockwise will take coordinates (x, y) and map them to (-y, x), negating the y-coordinate and swapping the x- and y-coordinates.

 A 90° rotation clockwise will map coordinates (x, y) to (y, -x), negating the x-coordinate and swapping the x- and y-coordinates.

Performing either of these would leave our image with a coordinate that needs negated, as well as needing to swap the coordinates back around.

This means we would have to perform the same rotation again; if we began with 90° clockwise, we would rotate 90 degrees clockwise again; if we began with 90° counter-clockwise, we would rotate 90 degrees counterclockwise again. Either way this rotates the figure a total of 180° and gives us the desired coordinates.

4 0

2 years ago

Read 2 more answers