SOLUTION: How do you solve 4x+5y=25 and 8x-5y=35 when using substitution

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Question 993532: How do you solve 4x+5y=25 and 8x-5y=35 when using substitution
Answer by ikleyn(52790) About Me  (Show Source):
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How do you solve  4x+5y=25  and  8x-5y=35 when using substitution.
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You can express  4x  from the first equation,  4x = 25-5y,  and then substitute it into the second equation.  You will get

2*(25-5y) - 5y = 35.

Simplify and solve:

50 - 10y - 5y = 35,
15y = 30 - 35,
15y = 15,
y = 1.

Now substitute the found value of  y=1  into the first equation to find  x.  You will get

4x + 5*1 = 25,
4x = 20,
x = 5.

Answer.  x = 5, y = 1.