How do you solve by substitution #3x-4y=-15# and # 5x+y=-2#?
1 Answer
Jun 7, 2015
(1) 3x - 4y = - 15
(2) 5x + y = - 2 --> y = - 5x - 2. Substitute this value into (1):
3x - 4(-5x - 2) = - 15
3x + 20x + 8 = - 15
23x = -23 ->
Check with equation (1): - 3 - 12 = - 15 . Correct.
