Question 1063213
Twice Martina's age decreased by Mario's age is 6. Three times Martina's age increased by twice Mario's is 23. What are the two numbers? 
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r - t = 6
3r + 2t = 23
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Modify for elimination:
2r - 2t = 12
3r + 2t = 23
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Add and solve for "r"::
5r = 35
r = 7 (Martina's age)
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Solve for "t"::
r - t = 6
7 - t = 6
t = 1 (Mario's age)
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Cheers,
Stan H.
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