SOLUTION: solve the following systems of equations x + 5y=2 3x + 19=y

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Question 443108: solve the following systems of equations x + 5y=2 3x + 19=y
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
Get in this form ax+by =c
-----------
x+5y=2
3x-y=-19
Multiply the the first by -3
-3x -15y =-6
3x -y = -19
Add the two together
0 + -16y = -25
y = 25/16
x + 5(25/16) = 2
x + 125/16 = 2
x = 32/16 - 125/16
x = -93/16
x = -93/16 y= 25/16
Let's check this:
Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++1%5Cx+%2B+5%5Cy+=+2%2C%0D%0A++++3%5Cx+%2B+-1%5Cy+=+-19+%29%0D%0A++We'll use substitution. After moving 5*y to the right, we get:
1%2Ax+=+2+-+5%2Ay, or x+=+2%2F1+-+5%2Ay%2F1. Substitute that
into another equation:
3%2A%282%2F1+-+5%2Ay%2F1%29+%2B+-1%5Cy+=+-19 and simplify: So, we know that y=1.5625. Since x+=+2%2F1+-+5%2Ay%2F1, x=-5.8125.

Answer: system%28+x=-5.8125%2C+y=1.5625+%29.


Which in decimal form is the same as before.