Martin needs help being a better friend and remembering how old his friends are. He can't remember their ages but he knows how to find their ages. He knows that Jennifer is three years less than twice his age. Sally is three years more than Martin. His friend, Gabby, is five years less than him.
Write an expression for Jennifer's, Sally's and Gabby's age, where x represents Martins age.
Jennifer:
Sally:
Gabby:

well first of martin needs some help cus he cants remember anything

Step-by-step explanation:

he needs new friends and a new life.

answer: 0.64

step-by-step explanation:

(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