SOLUTION: Hello For the life of me, i get different results with the substitution method, the textbook answer is -3, 2 Independent for the following: y = 3x + 11 3x + 3y = 0

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Question 62669This question is from textbook
: Hello
For the life of me, i get different results with the substitution method,
the textbook answer is -3, 2 Independent for the following:
y = 3x + 11
3x + 3y = 0

i come out with y= 11/4, x=11/4?????
This question is from textbook

Found 2 solutions by josmiceli, uma:
Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website!
I get y = 11/4 and x = -11/4
Just by observation, x and y have to be equal
in absolute value but opposite in sign for
the 2nd equation to be true.

Answer by uma(370) (Show Source):
You can put this solution on YOUR website!
Given y = 3x + 11
3x + 3y = 0
Plugging in y = 3x + 11 in the above we get,
3x + 3(3x+11) = 0
==> 3x + 9x + 33 = 0
==> 12x + 33 = 0
==> 12x + 33 - 33 = 0 - 33
==> 12x = - 33
==> 12x/12 = - 33/12
==> x = -11/4
So y = 3(-11/4) + 11
= -33/4 + 11
= (-33+44)/4 [taking LCD and adding]
= 11/4
x = - 11/4 and y = 11/4

Good Luck!!!