Use Pythagorean Theorem which states that in a right triangle:

, where a and b are the legs, and c is the hypotenuse.

Take the square root of both sides to solve for x.

The answer is 26.
The y intercept is the y value determined when x = 0
y = -0 - 5
y = - 5
The y intercept is (0,-5)
The x intercept is where y = 0
0 = -x - 5
5= -x
x = - 5
The x intercept is (- 5, 0)
First move the 2n over to the other side by subtracting it
so
4n=-8
then divide 4n by 4 and do the same to the other side
so
n= -8/4
n= -2
There are 714 boys in that school, you can cross multiply and divide to find the answer, if you wanna check. The way I wrote it was x (boys) / 1309 = 6/11.