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24 votes
24 votes
Solve by substitution I NEED STEP BY STEP
7x-y=34
2x+3y=-10

User Amras
by
2.5k points

1 Answer

17 votes
17 votes

Answer:

(4, - 6 )

Explanation:

7x - y = 34 ( multiply through by - 1 )

- 7x + y = - 34 ( add 7x to both sides )

y = 7x - 34 → (1)

2x + 3y = - 10 → (2)

substitute y = 7x - 34 into (2)

2x + 3(7x - 34) = - 10

2x + 21x - 102 = - 10

23x - 102 = - 10 ( add 102 to both sides )

23x = 62 ( divide both sides by 23 )

x = 4

substitute x = 4 into (1)

y = 7(4) - 34 = 28 - 34 = - 6

solution is (4, - 6 )

User Clayperez
by
2.9k points