algebra
posted by Anonymous on .
x+3y=10
7x5y=34
solve using substitution method

x+3y=10 ......(1)
7x5y=34 ......(2)
From (1), write it as:
x=103y ......(3)
Substitute x in (3) into (2)
7(103y)5y=34 .....(4)
Expand the left hand side
7021y5y=34
Isolate y
21y5y = 34 + 70
26y = 104
Calculate y:
y=104/26 = 4 .....(5)
Now substitute (5) into (3) to find x.
After that, substitute the values of x and y into equations (1) and (2) to verify if the solutions are correct. 
x=3y10
7(3y10)5y=34
21y705y=34
27y70=34
21y=104
y=104/21
this is your y value now just plug this value back into the x to find your x value
hope this helped.