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Solve using elimination. 10x + 8y = 12 4x + y = –15 ( , )

2 Answers

6 votes

Answer:

(-6,9)

Explanation:

Multiply 4x + y = -15 all the say through by -8 and then add to 10x + 8y = 12

-32x -8y = 120

10x + 8y = 12

-22x = 132 Divide both sides by -22

x = -6

Substitute -6 for x

4x + y = -15

4(-6) + y = -15

-24 + y = -15 Add 24 to both sides

y = 9


Check

10x + 8y = 12

10(-6) + 8(9) = 12

-60 + 72 = 12

12 = 12 checks

4x + y = -15

4(-6) + 9 = -15

-24 + 9 = -15

-15 = -15 Checks.

Helping in the name of Jesus.

User Pierre F
by
8.4k points
3 votes

Answer:

x = -6

Explanation:

you have given

10x + 8y = 12 and 4x + y = -15

so you must put the one var. x or y by same cofficent and in opposite sighn

so 10x + 8y = 12

- 8 (4x + y = -15 ) ......... i multiplied by -8

10x + 8y = 12

-32x - 8y = 120

then you will add the equation

(10x + 8y) + (-32x - 8y) = 12 + 120

afeter you simlify it u will get

-22x = 132

-22x = 132

x = -6 .... by dividing both sides by -22

User Eric Marcelino
by
8.3k points

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