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-x+2y=6
7/2x+7y=14 solve with substitution

1 Answer

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Answer:

(x, y) = (-1, 5/2)

Explanation:

The only variable with a coefficient that has a magnitude of 1 is x in the first equation. Using that equation, we can write an expression for x:

x = 2y -6

This can be substituted for x in the second equation.

(7/2)(2y -6) +7y = 14

7y -21 +7y = 14 . . . . . . eliminate parentheses

14y = 35 . . . . . . . . . . . add 21

y = 35/14 = 5/2 . . . . . divide by the coefficient of y

x = 2(5/2) -6 = -1

The solution is (x, y) = (-1, 5/2).

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