SOLUTION: One number is 3 more than twice the other number. If the sum of the two numbers is 21, find the two numbers.

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Question 1065122: One number is 3 more than twice the other number. If the sum of the two numbers is 21, find the two numbers.
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
Numbers are A and B (let A be the larger number)
A = 2B+3 (1)
A+B = 21 (2)
Subs for A in (2): (2B+3)+B = 21
3B + 3 = 21
3B = 18
B = 6
A=2B+3 = 2(6) + 3 = 12+3 = 15
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Ans:
The numbers are 6 and 15.
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Check: 6+15=21 (ok)
2*6+3 = 12+3 = 15 (ok)