SOLUTION: graph 30x+50y-100=0 3x-15y-30=0

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Question 229286: graph 30x+50y-100=0
3x-15y-30=0
Answer by drj(1380) About Me  (Show Source):
You can put this solution on YOUR website!
graph
30x+50y-100=0 or 30x+50y=100
3x-15y-30=0 or 3x-15y=30

Step 1. The graph of the two lines are shown below:

graph%28400%2C400%2C+-10%2C+10%2C+-10%2C+10%2C+-3x%2F5%2B2%2C+x%2F5-2%29

Step 2. The intersection point is (-1,5) or x=-1 and y=5

Step 3. As a check, solve using substitution

Solved by pluggable solver: SOLVE linear system by SUBSTITUTION
Solve:
+system%28+%0D%0A++++30%5Cx+%2B+50%5Cy+=+100%2C%0D%0A++++3%5Cx+%2B+-15%5Cy+=+30+%29%0D%0A++We'll use substitution. After moving 50*y to the right, we get:
30%2Ax+=+100+-+50%2Ay, or x+=+100%2F30+-+50%2Ay%2F30. Substitute that
into another equation:
3%2A%28100%2F30+-+50%2Ay%2F30%29+%2B+-15%5Cy+=+30 and simplify: So, we know that y=-1. Since x+=+100%2F30+-+50%2Ay%2F30, x=5.

Answer: system%28+x=5%2C+y=-1+%29.



which yields the same result with x=5 and y=-1.

I hope the above steps were helpful.

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

And good luck in your studies!

Respectfully,
Dr J
http://www.FreedomUniversity.TV