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Solve the system using elimination. 5 x + 4 y = 12 3 x – 3 y = 18

User Vanagar
by
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1 Answer

3 votes

Answer:

x = 4 , y = -2

Explanation:

Solve the following system:

{5 x + 4 y = 12 | (equation 1)

3 x - 3 y = 18 | (equation 2)

Subtract 3/5 × (equation 1) from equation 2:

{5 x + 4 y = 12 | (equation 1)

0 x - (27 y)/5 = 54/5 | (equation 2)

Multiply equation 2 by 5/27:

{5 x + 4 y = 12 | (equation 1)

0 x - y = 2 | (equation 2)

Multiply equation 2 by -1:

{5 x + 4 y = 12 | (equation 1)

0 x+y = -2 | (equation 2)

Subtract 4 × (equation 2) from equation 1:

{5 x+0 y = 20 | (equation 1)

0 x+y = -2 | (equation 2)

Divide equation 1 by 5:

{x+0 y = 4 | (equation 1)

0 x+y = -2 | (equation 2)

Collect results:

Answer: {x = 4 , y = -2

User JamesDullaghan
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6.4k points