Can someone help me please

Question

Kyle is asked to solve a system of equations by substitution:

2x + 3y = 12
x - 2y = 4

Which step should Kyle take first? Why?
A) Kyle should solve the first equation for y because 12 is divisible by 3.
B) Kyle should solve the second equation for y because y is being subtracted.
C) Kyle should solve the second equation for x because x has a coefficient of 1.
D) Kyle should solve the first equation for x because x has a coefficient greater than 1.

Answer 1

When solving a system of equations by substitution, I would isolate the variable that takes the least amount of work.

 

In this case, that means isolate the x in the 2nd equation since all you have to do is add 2y to both sides.

 

Therefore, the answer is C) Kyle should solve the second equation for x because x has a coefficient of 1.