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Solve by using elimination 7) -6x – 8y = -30
4x + 2y = 20​

User Greg Oks
by
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1 Answer

3 votes

Answer:

x = 5 , y = 0

Step-by-step explanation by elimination:

Solve the following system:

{-6 x - 8 y = -30 | (equation 1)

4 x + 2 y = 20 | (equation 2)

Add 2/3 × (equation 1) to equation 2:

{-(6 x) - 8 y = -30 | (equation 1)

0 x - (10 y)/3 = 0 | (equation 2)

Divide equation 1 by -2:

{3 x + 4 y = 15 | (equation 1)

0 x - (10 y)/3 = 0 | (equation 2)

Multiply equation 2 by 3/10:

{3 x + 4 y = 15 | (equation 1)

0 x - y = 0 | (equation 2)

Multiply equation 2 by -1:

{3 x + 4 y = 15 | (equation 1)

0 x+y = 0 | (equation 2)

Subtract 4 × (equation 2) from equation 1:

{3 x+0 y = 15 | (equation 1)

0 x+y = 0 | (equation 2)

Divide equation 1 by 3:

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

0 x+y = 0 | (equation 2)

Collect results:

Answer: {x = 5 , y = 0

User Abbafei
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