Width = x
length = x+10
Area of deck = 144 square feet
Area = length * width
144 = x(x+10)
Solving for x in a quadratic:
x²+10x = 144
x²+10x-144 = 0
Factor:
(x+18)(x-8) = 0
Solving for x:
x = 8, x = -18
Dimensions cannot be negative, therefore x = 8, only.
Length = x + 10
Length = 18
Width = 8
We can reject the last one: subtracting a non-zero value will result in a smaller value.
So now we have:
<span>2(A + B)
(A + B)2
A2 + B2
If all of them are mulptiplications, then they are all equivalent!
I mean by this, if what you meant is this:
</span>
<span>2*(A + B)
(A + B)*2
A*2 + B*2
If there is no sign, then the multiplication sign is implicit,
and all of these expressions say exactly the same: two of A and two of B.
</span>
What exactly are you asking?