Question 1(Multiple Choice Worth 1 points) (04.02 LC)

For the following system, if you isolated x in the first equation to use the substitution method, what expression would you substitute into the second equation?

−x + 2y = −6
3x + y = 8

−2y + 6
2y − 6
2y + 6
−2y − 6

your answer is b.

x = 33.9

y = 65.6

step-by-step explanation:

a and c

for infinitely many solutions we require both left and right sides to be equal

distribute and simplify

a

14 - 8x = 20 - 8x - 6 = 14 - 8x ← both sides equal so infinite solutions

b

6x - 54 = 6x - 54 + x = 7x - 54 ← not equal

c

4x + 16 = 4x + 10 + 6 = 4x + 16 ← both sides equal so infinite solutions

d

5x - 40 + 10 = 5x + 10

5x - 30 = 5x + 10 ← not equal