Question

The line given by -18x+7y=21 is dilated by a scale factor centered at the origin. The image of the line after dilation is given by y= 18/7x+6. What is the scale factor of the dilation?

Answer 1

Answer:

3 units in the vertical direction

Step-by-step explanation:

-18x + 7y = 21 → 7y = 18x + 21 → y = 18/7x + 3

6-3=3

Answer 2

Answer:

2

Step-by-step explanation:

$-18x+7y=21\\\\\implies y=\dfrac{18}{7}x+3$

when x = 0, y = 3

$y=\dfrac{18}{7}x+6$

when x = 0, y = 6

Therefore, the scale factor is 2 since the y coordinate has double: 3 x 2 = 6