SOLUTION: systems of equations; x-y=7 4x-5y=25 find boh x and y

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Question 415207: systems of equations;
x-y=7
4x-5y=25
find boh x and y
Answer by yass99(1) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by substitution
x = 7+y
Subsitute this equation in 4x-5y = 25
4(7+y) -5y = 25
28 + 4y -5y = 25
28 - y = 25
Move the y to the other side and bring the 25 to the opposite side
28-25 = y
y = 3
Substitue this in x-y = 7
x - 3 = 7
x = 7=3
x = 10