Answer:
Step-by-step explanation:
x + y = -20......multiply by -6
6x - 5y = -20
-----------------
-6x - 6y = 120 (result of multiplying by -6)
6x - 5y = -20
---------------add
-11y = 100
y = -100/11 <======
x + y = -20
x + (-100/11) = -20
x - 100/11 = -20
x = -20 + 100/11
x = -220/11 + 100/11
x = - 120/11 <========
solution is : x = -100/11 and y = -120/11 or (-120/11 , -100/11)