Question

7. Which method would be the most efficient to solve the system? y = 1/2x, 2x + 3y = 28
A) graphing
B) substitution
C) elimination
D) distributive

Answer 1

y = ¹/₂x
2x + 3y = 28

     2x + 3y = 28
2x + 3(¹/₂x) = 28
   2x + 1¹/₂x = 28
           3¹/₂x = 28
            3¹/₂    3¹/₂
                 x = 8
y = ¹/₂x
y = ¹/₂(8)
y = 4
(x, y) = (8, 4)
The method would be a substitution method (the answer is B).