in order to slove the following system of equations by addition, which of the following could you do before adding the equations so that one variable will be eliminated when you add them? 4x-2y=7 3x-3y=15

the forst and 3rd

step-by-step explanation:

-2 is the right

5050

hope this !

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have