Answer:
a = 12
b = 9
Explanation:
b = 3/4(a)
9 = 3/4(12)
9 = 9
a + b = 21
9 + 12 = 21
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b = 3/4(a)
-16(1/4) = (3/4) ((37(1/4))
-16 (1/4) = 447/16
False
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a + b = 21
20 + 11 = 21
31 = 21
False
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a + b = 21
20 + 15 = 21
35 = 21
False
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The only correct one was a = 12; b = 9
I hope this helps!