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NEED HELP ASAP

x+y= 2
-3x + 4y = 15

User David King
by
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1 Answer

5 votes

Answer:

x = - 1 , y = 3

Explanation:

given the system of equations

x + y = 2 → (1)

- 3x + 4y = 15 → (2)

multiplying (1) by 3 and adding to (2) will eliminate x

3x + 3y = 6 → (3)

add (2) and (3) term by term to eliminate x

(- 3x + 3x) + (4y + 3y) = 15 + 6

0 + 7y = 21

7y = 21 ( divide both sides by 7 )

y = 3

substitute y = 3 into either of the 2 original equations and solve for x

substituting into (1)

x + 3 = 2 ( subtract 3 from both sides )

x = - 1

the solution is x = - 1, y = 3

User Ankit Vadariya
by
7.6k points