SOLUTION: How do you find an answer to the question: 3x+y=3 7x+2y=1

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Question 143503This question is from textbook algebra 1
: How do you find an answer to the question:
3x+y=3
7x+2y=1
 This question is from textbook algebra 1

Answer by nabla(475) About Me  (Show Source):
You can put this solution on YOUR website!
The quickest way would be to subtract the first equation from the second giving you a new system:
3x+y=3
4x+y=-2
Now you can repeat that, giving another system:
3x+y=3
x=-5
Now plug the solution for x into the first equation:
3(-5)+y=3 implies y=18
set: (-5,18)
Here is another way to do it:
Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++3%5Cx+%2B+1%5Cy+=+3%2C%0D%0A++++7%5Cx+%2B+2%5Cy+=+1+%29%0D%0A++We'll use substitution. After moving 1*y to the right, we get:
3%2Ax+=+3+-+1%2Ay, or x+=+3%2F3+-+1%2Ay%2F3. Substitute that
into another equation:
7%2A%283%2F3+-+1%2Ay%2F3%29+%2B+2%5Cy+=+1 and simplify: So, we know that y=18. Since x+=+3%2F3+-+1%2Ay%2F3, x=-5.

Answer: system%28+x=-5%2C+y=18+%29.