Question

A figure has been dilated from center 𝑂 by a scale factor of 𝑟 = 5/8. What scale factor would return the dilated figure back to the original size?

Question 2 options:



a)

r=58




b)

r=85




c)

r=8




d)

r=5

Answer 1

plzz help ill fan

Answer 2

just find the reciprocal of the scaling factor

Answer 3

to check use

scaling factor x reciprocal = 1

Answer 4

idk how to do that

Answer 5

all you do is take your scaling factor and flip the fraction

Answer 6

uhh so 8/5?

Answer 7

yes

Answer 8

check by multiplying the fractions 5/8 x 8/5 = 1..?

Answer 9

oh ok thank you :)

Answer 10

This so called "scaling factor" can also be called a "multiplicative inverse."

In your question, it is the number you need to find to get the figure back to the scale of 1.

"A figure has been dilated from the centre 𝑂 by a scale factor of a𝑟 = 5/8." <---that means the figure started at the scale of 1 and was multiplied by 5/8.

"What scale factor would return the dilated figure back to the original size?" <---you are asked to find the "multiplicative inverse" that will, when multiplied by 5/8 , give you the original scale factor of 1.

$$\huge \dfrac{5}{8}•?=1$$

Answer 11

Note: if the question was a figure has been dilated from center 𝑂 by a scale factor 0. What scale factor would return the dilated figure back to the original size?

Your answer would be no scale factor would return the dilated figure back to the original size, because multiplying by 0 would make the figure disappear.

There exists no number that when multiplied by 0 will give you the original size of 1. Since 0 times any number is 0, not 1.

This^ is why division by 0 is undefined.