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Solve the following system of equations.
0.06x +0.32 y= 0.28
0.07x-0.08y=-0.58

User Bestter
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1 Answer

3 votes

Answer:

x = - 6 , y = 2

Explanation:

given the system of equations

0.06x + 0.32y = 0.28 ( multiply through by 100 to clear the decimals )

6x + 32y = 28 → (1)

0.07x - 0.08y = - 0.58 ( multiply through by 100 to clear the decimals )

7x - 8y = - 58 → (2)

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

28x - 32y = - 232 → (3)

add (1) and (3) term by term to eliminate y

(6x + 28x) + (32y - 32y) = 28 - 232 , that is

34x + 0 = - 204

34x = - 204 ( divide both sides by 34 )

x = - 6

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

substituting into (2)

7(- 6) - 8y = - 58

- 42 - 8y = - 58 ( add 42 to both sides )

- 8y = - 16 ( divide both sides by - 8 )

y = 2

solution is x = - 6 , y = 2

User Joe Bathelt
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