SOLUTION: 3x+y=-5 y=x+3 sove by sobstitution. express our answer

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Question 224068: 3x+y=-5 y=x+3 sove by sobstitution. express our answer
Found 3 solutions by LtAurora, drj, stanbon:
Answer by LtAurora(115) About Me  (Show Source):
You can put this solution on YOUR website!
The second given equation is already solved for y, so we can plug this equation into the first to obtain:
3x%2B%28x%2B3%29=-5. The second equation is simply put in the place of the y in the first equation.
To solve this, combine the x terms on the left hand side of the equation:
4x%2B3=-5.
Then, subtract the 3 from both sides:
4x=-8.
To obtain what x equals, divide both sides by 4:
x=-2.
This result can then be plugged back into the second equation to determine that y is equal to.
So:
y=-2%2B3
Which yields: y=1.
Our answer is then x=-2, y=1.

Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
3x+y=-5
y=x+3 or -x+y=3

Solve by substitution.

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++3%5Cx+%2B+1%5Cy+=+-5%2C%0D%0A++++-1%5Cx+%2B+1%5Cy+=+3+%29%0D%0A++We'll use substitution. After moving 1*y to the right, we get:
3%2Ax+=+-5+-+1%2Ay, or x+=+-5%2F3+-+1%2Ay%2F3. Substitute that
into another equation:
-1%2A%28-5%2F3+-+1%2Ay%2F3%29+%2B+1%5Cy+=+3 and simplify: So, we know that y=1. Since x+=+-5%2F3+-+1%2Ay%2F3, x=-2.

Answer: system%28+x=-2%2C+y=1+%29.



ANSWER: The solution is (-2,1) or x=-2 and y=1.

I hope the above steps and explanation were helpful.

For Step-By-Step videos on Introduction to Algebra, please visit http://www.FreedomUniversity.TV/courses/IntroAlgebra and for Trigonometry please visit http://www.FreedomUniversity.TV/courses/Trigonometry.

Also, good luck in your studies and contact me at john@e-liteworks.com for your future math needs.

Respectfully,
Dr J

http://www.FreedomUniversity.TV

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
3x+y=-5
y=x+3
solve by substitution.
------------------
Substitute for "y" and solve for "x":
3x + x+3 = -5
4x = -8
x = -2
-------
Substitute into y = x+3 to solve for "y":
y = -2+3 = 1
==================
Cheers,
Stan H.