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A first number plus twice a second number is 8. Twice the first number plus the second totals 28. Find the numbers.

1 Answer

3 votes

Answer:

x = 16, y = -4

Explanation:

First, we can say that "x = the first number" and "y = the second number"

The first number plus twice the second number is 8:

x + 2y = 8

Twice the first number plus the second number totals 28:

2x + y = 28

Next, we solve the system of equations.

x + 2y = 8 ---> 2x + 4y = 16 ---> 2x = 16 - 4y

2x + y = 28 ---> 2x = 28 - y

16 - 4y = 28 - y

-4y + y = 28 - 16

-3y = 12

y = -4

Now, we plug "y = -4" into either one of the equations to find x:

x + 2(-4) = 8

x + -8 = 8

x = 8 + 8

x = 16

User Ronald P Mathews
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