Question

Triangle RST has a perimeter of 21 feet. What is the value of x?

*
5 points

A.x = 2
B.x = 3
C.x = 4
D.x = 5

Answer 1

Answer: 5


Explanation:
x + x + 2 + x + 4 = 21
3x + 6 = 21
-6 -6
3x = 15
3x/3 =15/3
x = 5

Answer 2

Choice D is the correct answer.

Explanation:

The perimeter of a shape is just the sum of all the sides. Therefore, if the perimeter is 21 ft, we can set up the following equation:

(x) + (x + 2) + (x + 4) = 21

Now solve out the equation!

3x + 6 = 21

3x = 15

x = 5

Therefore, the correct answer is choice D.

Hope this helps!