Please help me, i don’t understand this question nor how to do it

Step-by-step explanation:

See attached picture.

First, compare the highest term of the dividend (x²) to the highest term of the divisor (x).  We need to multiply the divisor by x.

When we do that, we get x² + 5x.  Subtracting this from the dividend, we get -9x + 11.

Now repeat the process.  Compare the highest term of the new dividend (-9x) to the highest term of the divisor (x).  We need to multiply by -9.

When we do that, we get -9x − 45.  When we subtract from the new dividend, we get 56.

So the quotient is x − 9, and the remainder is 56.

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240