Question 56807This question is from textbook college algebra
:
I am solving by addition method. These two equations have a bracket at the left end emcompassing both of the equations.
{2x + 3y =8
{-5x + y = -3
remember the bracket at the left encompassing both equations. I can't draw one to go for both lines.
my attempt
{2x + 3y =8 15x+10y=40
{-5x +y =-3 50x-10y= 30
------------------65x = 70
---------------------x= 1.76
Then i have to plug back in to the equation:
2x + 3y =8
2(1.76)+3y =8
3.52 + 3y =8
3y=4.48
y= 1.49
Is this correct? Help!
This question is from textbook college algebra
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! {1st: 2x + 3y =8
{2nd: -5x + y = -3
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Multiply 2nd by 3 to get:
3rd: -15x+3y=-9
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Subtract 3rd from 1st to get:
17x=17
x=1
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Substitue into 1st or 2nd to solve for y:
2(1)+3y=8
3y=6
y=2
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Check the solution: x=1, y=2 in 2nd.
-5(1)+2=-3
-5+2=-3
-3=-3
It checks.
So the solution for the system is (1,2)
Cheers,
Stan H.
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