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Solve the following linear system by elimination. Check your solution:

1. x + 5y =4
2. 4x + 12y = 8

Solve the following linear system by elimination. Check your solution: 1. x + 5y =4 2. 4x-example-1
User Nathan Day
by
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1 Answer

4 votes

Answer:

(- 1, 1 )

Explanation:

x + 5y = 4 → (1)

4x + 12y = 8 → (2)

multiplying (1) by - 4 and adding to (2) will eliminate x

- 4x - 20y = - 16 → (3)

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

0 - 8y = - 8

- 8y = - 8 ( divide both sides by - 8 )

y = 1

substitute y = 1 into either of the 2 equations and solve for x

substituting into (1)

x + 5(1) = 4

x + 5 = 4 ( subtract 5 from both sides )

x = - 1

As a check

substitute these values into the left side of both equations and if equal to the right side then they are the solution.

- 1 + 5(1) = - 1 + 5 = 4 = right side

4(- 1) + 12(1) = - 4 + 12 = 8 = right side

(- 1, 1 ) is the solution to the system of equations

User Rob Anthony
by
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