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Solve using substitution.

–7x − 9y = 11
5x + 6y = –4

User Filofel
by
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1 Answer

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Answer: x=10, y=-9

Explanation:

1. isolate y

-9y=11+7x

y=-11/9 -7x/9

2. plug y into 2nd equation

5x + 6(-11/9 -7x/9)=-4

5x - 22/3 - 14x/3 =-4

3. solve for x

15x/3 - 14x/3 = 10/3

x/3=10/3

x=10

4. use x for solve for y

-7(10) - 9y = 11

-70 - 9y =11

-9y = 81

y=-9

i hope this helps

User Zwickilton
by
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