3( 2p - 5) - 6p
need help please​

15

Step-by-step explanation:

We have the expression 3(2p - 5) - 6p and are asked to simplify.

Let's distribute, which is to multiply a number that is outside of a parenthesis bracket by the numbers inside the parenthesis.

3(2p - 5) - 6p

(3(2p) - 3(5)) - 6p

6p - 15 - 6p

Since you can only do changes to like terms and 15 and 6p are two different terms, we do 6p - 6p.

6p - 6p

0

Leaving us with 15.

-15

Step-by-step explanation:

Simplify each term.

6p - 15 - 6p

Combine the opposite terms:

Subtract 6p from 6p

0 - 15

Subtract 0 from 15

-15

good luck, hope this helps :)

(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