How do you solve $7 x - 2 y = 8$ $7x-2y=8$ and $5 x + 2 y = 4$ $5x+2y=4$ using substitution?

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Answer 1 · 2018-05-07T12:39:01

Find $2 y$ $2y$ in the first and put the value in the second equation

$7 x - 8 = 2 y$ $7x-8 = 2y$ after arranging the first original equation. Put this into the second

$5 x + 2 y = 4$ $5x + 2y = 4$

$5 x + 7 x - 8 = 4$ $5x + 7x - 8 = 4$

$12 x = 4 + 8$ $12x = 4+8$

$x = \frac{12}{12} = 1$ $x = 12/12 = 1$

Now find y.

$2 y = 7 x - 8$ $2y=7x-8$

$2 y = 7 - 8$ $2y = 7-8$

$2 y = - 1$ $2y = -1$

$y = - \frac{1}{2}$ $y=-1/2$

Your answer is $x = 1$ $x=1$ and $y = - \frac{1}{2}$ $y=-1/2$

How do you solve 7x−2y=87x-2y=8 and 5x+2y=45x+2y=4 using substitution?