SOLUTION: Trying to solve by substitution method. 4x + 7y = 36 x = 19 - 3y

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Question 254721: Trying to solve by substitution method.
4x + 7y = 36
x = 19 - 3y
Found 2 solutions by drk, jim_thompson5910:
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
Trying to solve by substitution method.
(i) 4x+%2B+7y+=+36
(ii) x+=+19+-+3y
substitute (ii) into (i) to get
(iii) 4%2819-3y%29+%2B+7y+=+36
76+-+12y+%2B+7y+=+36
-5y+=+-40
y = 8. Find x using (ii). We get
x = 19- 24 = -5
(-5, 8)

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
4x+%2B+7y+=+36 Start with the first equation.


4%2819+-+3y%29+%2B+7y+=+36 Plug in x+=+19+-+3y


76-12y%2B7y=36 Distribute.


-5y%2B76=36 Combine like terms on the left side.


-5y=36-76 Subtract 76 from both sides.


-5y=-40 Combine like terms on the right side.


y=%28-40%29%2F%28-5%29 Divide both sides by -5 to isolate y.


y=8 Reduce.


x+=+19+-+3y Go back to the second equation


x+=+19+-+3%288%29 Plug in y=8


x+=+19+-+24 Multiply


x+=+-5 Subtract



So the solutions are x=-5 and y=8 giving us the ordered pair (-5,8)