Mathematics
Wiatrowski132
26

the sum of two numbers is 15 less than twice the first number their difference is 5 less than twice the second number.  Find the number

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(2) Answers
roxxi

[latex]2n-15=5-2n[/latex] [latex]4n=20[/latex] [latex]\frac{4n}{4}=\frac{20}{4}[/latex] [latex]n=5[/latex] The number is 5

Polieke

x --- first number y --- second number x + y = 2x - 15 x - y = 2y - 5 x - 2x + y = -15 x - y - 2y = - 5 -x + y = -15 x - 3y = - 5 ----------------- -2y = -20  /:(-2) y = 10 x - 3y = - 5   ⇒  x = - 5 + 3y = - 5 + 3 · 10 = - 5 + 30 = 25 Ans.: x = 25 y = 10

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