SOLUTION: d+e-f=10 e=f+d+2 f=2e-7 Solve with substitution

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Question 766400: d+e-f=10
e=f+d+2
f=2e-7
Solve with substitution

Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
First using the f= equation, having only two of the variables, to substitute into the first two equations may be easiest.
d+e+(2e-7)=10 and e=(2e-7)+d+2
d+3e-7=10 and e=2e+d-5
d+3e=17 and 0=e+d-5
d=17-3e.
Let's use this formula for d and substitute into the 0= equation.

0=e+(17-3e)-5
0=-2e+17-5
-2e=5-17
2e=17-5=15
e=15%2F2

Maybe now would be easiest to find f.
f=2(e)-7 and you just found e...
...
continue...?