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2 votes
-2x+5y=-42

7x+2y= 30
solve using substitution or elimination
classify the system of equations

User Bob Yexley
by
5.0k points

1 Answer

3 votes

Answer:

(6, - 6 )

Explanation:

solving using the elimination method

- 2x + 5y = - 42 → (1)

7x + 2y = 30 → (2)

multiplying (1) by 7 and (2) by 2 and adding will eliminate x

- 14x + 35y = - 294 → (3)

14x + 4y = 60 → (4)

add (3) and (4) term by term to eliminate x

0 + 39y = - 234

39y = - 234 ( divide both sides by 39 )

y = - 6

substitute y = - 6 into either of the 2 equations and solve for x

substituting into (2)

7x + 2(- 6) = 30

7x - 12 = 30 ( add 12 to both sides )

7x = 42 ( divide both sides by 7 )

x = 6

solution is (6, - 6 )

User Swantewit
by
3.6k points