Question 255769: write an equation for the sentence: Lisa is five years older than her sister and the sum of their ages is 19 Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! write an equation for the sentence: Lisa is five years older than her sister and the sum of their ages is 19
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Equations:
L = S + 5
L + S = 19
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Substitute for L and solve for S:
S+5 + S = 19
2S = 14
S = 7 (Her sister's age)
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Since L = S+5, L = 7+5 = 12 (Lisa's age)
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Cheers,
Stan H.
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