Answer:
a = 1
b = 5
Explanation:
a + 2b = 11
(a - b = -4) × 2
2a - 2b = -8
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a + 2b = 11
2a - 2b = -8
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3a = 3
÷3 ÷3
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a = 1
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a - b = -4
1 - b = -4
-1 -1
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-b = -5
÷-1 ÷-1
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b = 5
I hope this helps!