7/10 m= 0.7 m
4.1÷0.7=5.85
You would round down 5.85 to just 5, because he cannot cut less than a whole strip.
To find the exact amount of wire used in 5 strips:
5×0.7= 3.5
4.1-3.5= 0.6 m will be leftover.
Divide f(x) by x + 15
this comes to 2x^2 - 6 which represents the length