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-3x-3y=3 solve by substitution

User Biera
by
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1 Answer

3 votes

Answer: x = 2, y = -3

Step-by-step explanation: From the question,

-3x -3y = 3 ---------- this becomes the first equation

Make y the subject

-3y = 3 + 3x

y = (3 + 3x)/ -3 ----------this becomes our second equation

Substitute the value of y into the first equation

-3x -3(3 + 3x) = 3

-3x -9 + 9x = 3

Collect like terms

-3x + 9x = 3 + 9

6x = 12

Divide both sides by 6

6x/ 6 = 12/ 6

x = 2

Substitute x = 2 into the second equation to find y

y = (3 + 3(2) )/ -3

y = ( 3 + 6) / -3

y = 9/ -3

y = -3

User Ahmad Maleki
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