Question

Solve the system by the substitution method. *-2x + y = 93x – 7y = 3(-3,4)(2,-4)(-6, -3) (-1,-7)

Answer 1

-2x + y = 9 (eq. 1)

3x - 7y = 3 (eq. 2)

Isolate y in the first equation, as follows:

y = 9 + 2x (eq. 3)

Replace this in the second equation:

3x - 7(9 + 2x) = 3

3x - 7*9 - 7*2x = 3

3x - 63 - 14x = 3

-11x = 3 + 63

x = 66/(-11)

x = -6

Replacing this result into the third equation:

y = 9 + 2*(-6)

y = -3

Then, the answer is (-6, -3)