Question

Write as an equation: The sides of a triangle are 7, x and (x + 1). The perimeter is 30.

A. 30 =7+ (x+1)
B. 30 - 7 = 2x
C. 30 = 7 + 2(x + 1)
D.30 = 8+2x

Answer 1

D

Explanation:

Perimeter = addition of all sides

30 = 7 + x + x + 1

30 = 8 + 2x

Collecting like terms

30 - 8 = 2x

22 = 2x

Dividing by 2

22/2 = 2x/2

11 = x

Answer 2

d

This is because 7+x+1=30 (this is the equation btw).

You combine the like terms so you get 30=8+2x (7+1 and x+x)

do the equation so you get:

30=8+2x

-8 -8

22=2x

divide both sides by 2

11=x