Answer:
x = 3
Step-by-step explanation:
First, you will pick the first equation :
(x*20)
Then the next,
(x*20) + 5
Then the last equation,
(x*20) + 5 = 5*13
Then you solve
20x + 5 = 65
20x = 65 - 5
20x = 60
20x/20 = 60/20
x = 3
It's going to be kind of crazy, but you need to use Pythagorean's Theorem for this. That will look like this:

. FOIL out the left side to get

. FOIL out the first of the 2 expressions on the right to get

, and the second of the 2 to get 4x. Our equation now looks like this:

. Combine like terms to get an equation that still has square roots in it that we have to deal with:

and

. We will square both sides to get rid of the square root sign.

. This is a polynomial now that can be factored to solve for x. Bring the 2x over by subtraction and set the polynomial equal to 0.

. Factor out an x, leaving us with x(x-2)=0. That means that x = 0 or x - 2 = 0 and x = 2. Of course if we are solving for the length of a side we know it can't have a side length of 0, so it must have a side length that is a multiple of 2. x = 2
Answer: I think it's C
Step-by-step explanation:
Answer:10
Step-by-step explanation:
6+4=10