Determine the value of X

Mathematics

1 answer:

dolphi86 [110]2 years ago

6 0

Answer:

The value of x is 15 ⇒ answer D

Step-by-step explanation:

* Lets talk about dilation

- A dilation is a transformation that changes the size of a figure.

- It can become larger or smaller, but the shape of the

figure does not change.

- The scale factor, measures how much larger or smaller

the image will be

- If the scale factor greater than 1, then the image will be larger

- If the scale factor between 0 and 1, then the image will be smaller

- If the scale factor is negative then the figure will reflected

* Now lets solve the problem

∵ D (o, k) (x , 9) → (-10 , -6)

- D means dilation

- o means the center of dilation is the origin

- k means the scale factor of dilation

∵ The y-coordinate of the point is 9

∵ The image has y-coordinate -6

∵ The image = The scale factor × the coordinates

∴ -6 = k × 9 ⇒ divide both sides by 9

∴ k = -6/9 = -2/3

- Lets find x by same way

∵ -10 = -2/3 × x ⇒ divide both sides by -2/3

∴ x = -10 ÷ (-2/3) ⇒ change the division to multiplication

∴ x = -10 × (-3/2) = 30/2 = 15

∴ The x-coordinate of the point before dilation is 15

* The value of x is 15

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