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4 votes
Solve each system by substitution.
x+8y=-15
7x + 8y=-9​

1 Answer

7 votes

Answer:

(1,-2)

Explanation:

x+8y=-15

7x+8y=-9

put x in right and make it a -

8y=-15-x

7x+8y=-9

use 8y to substitute into an equation

7x-15-x=-9

subtract 7x to x

6x-15=-9

add 15 to -9

6x=6

divide both sides by 6

x=1

substitute 1 to an equation

7x+1+8y=-9

solve

y=-2

(1,-2)

User Alexander Shostak
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