Answer:
Step-by-step explanation:
Given the equations:
4c-d = f ....... 1
d = c-e....... 2
f = d + e....... 3
Substitute 2 into 1
4c -(c-e) = f
4c -c + e =f
3c + e = f ......4
Substitute equation 3 into 4:
3c+e = d+e
subtract e from both sides
3c+e-e = d+e-e
3c = c (Proved)
