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3 years ago

Solve the following system of equations algebraically: 4x - 5y = 18 3x – 2y = 10

Mathematics

1 answer:

fiasKO [112]3 years ago

8 0

Answer:

Step-by-step explanation:

Given the 2 equations

4x - 5y = 18 → (1)

3x - 2y = 10 → (2)

Multiplying (1) by 3 and (2) by - 4, then adding will eliminate the x- term

12x - 15y = 54 → (3)

- 12x + 8y = - 40 → (4)

Add (3) and (4) term by term to eliminate x, that is

- 7y = 14 ( divide both sides by - 7 )

y = - 2

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

Substituting into (1)

4x - 5(- 2) = 18

4x + 10 = 18 ( subtract 10 from both sides )

4x = 8 ( divide both sides by 4 )

x = 2

solution is (2, - 2 ) → D

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