SOLUTION: I have a question on solving a problem on (solving systems using substitution) the problem is: y=5x+5 y=15x-1 (solve using substitution)

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Question 106105: I have a question on solving a problem on (solving systems using substitution)
the problem is: y=5x+5
y=15x-1 (solve using substitution)

Answer by Fombitz(13823) About Me  (Show Source):
You can put this solution on YOUR website!
When you solve by subsitution, you use one equation to solve for one of the unknown variables and then substitute that solution in your other equation.
1.y=5x%2B5
2.y=15x-1
Let's use equation 1 and substitute the value for y in equation 2.
2.y=15x-1
%285x%2B5%29=15x-1 Substitute for y using Eq. 1.
5x%2B5-15x=15x-15x-1 Use the additive inverse of 15x.
-10x%2B5=-1
-10x%2B5-5=-1-5 Use the additive inverse of 5.
-10x=-6
-10x%2F%28-10%29=-6%2F-10 Multiplicative inverse of -10.
x=6%2F10Simplify.
x=3%2F5Lowest terms.
Now that you have a value for x, plug the value into either Equation 1 or Equation 2 and solve for y.
1.y=5x%2B5
y=5%283%2F5%29%2B5
y=3%2B5
y=8
Always check your answers.
1.y=5x%2B5
8=5%283%2F5%29%2B5
8=3%2B5
8=8
Good answer.
2.y=15x-1
8=15%283%2F5%29-1
8=9-1
8=8
Good answer.
Your solution is x=3/5, y=8.