Question 1017190
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L=number of loonies; T=number of toonies
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L+T=36
L=36-T . Use this to substitute for L below. 
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$1L+$2T=$56 . Substitute for L from above.
$1(36-T)+$2T=$56
$36-$1T+$2T=$56
$1T=$20
T=20
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L=36-T=36-20=16
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ANSWER: She has 16 loonies and 20 toonies.
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CHECK:
$1L+$2T=$56
$1(16)+$2(20)=$56
$16+$40=$56
$56=$56
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