Answer:
-45
Step-by-step explanation:
-100 + -80 = 6x + -2x
-180 = 4x
-180/4 = -45
x= -45
-100 + 2x = 80 + 6x
-80 - 2x = -80 -2x
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-180 + 0 = 0 + 4x
-180/4 = x
-45 = x
