A) length= w+5
width=w
perimeter=42mm
B) 2(w+5)+2w>42
2w+10+2w>42
4w>32
w>8
The width should be greater than 8 and the length should be more than 13.
Hope this helps!
<span>Difference of squares method is a method that is used to evaluate the difference between two perfect squares.
For example, given an algebraic expression in the form:
can be factored as follows:

From the given expressions, the only expression containing two perfect squares with the minus sign in the middle is the expression in option A.
i.e.

which can be factored as follows:

.</span>
U= 9.4m/s
v= -7.4m/s (Negative sign because it is in the opposite direction as he is rolling back)
t= ?
s= ?
a= ?
Now, a= v-u/t
= -7.4-9.4÷3
=-5.6
By the second equation of motion.
s= ut+1÷2at*2 ( *2 is the power)
s= 9.4×3+1÷2×-5.6×3*2
= 28.2 +(-25.2)
=3
Therefore s or the distance travelled is 3m.