Step-by-step explanation:
1 . x - 4y = -10
2x + y = -11
multiply the first equation with 2
2x - 8y = -20
-
2x + y = -11
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= 0 - 9y = -9
y = 1
x = -6
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2.
a - 3b = 24
-
a + 2b = -16
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= 0- 5b = 40
b = - 8
a = 0
and so on
