Question

The first side of a triangle measures 4 in. less than the second side, the third side is 3 in. more than the first side, and the perimeter is 15 in. How long is the third side? If s represents the length of the second side, which of the following represents the length of the third side?

Answer 1

The third side would equal 7. To get the answer write the equation s - 4 + s + 3 = 15. Combine like terms (s + s) and (-4 + 3) which equals 2s - 1 = 15. Add 1 to each side of the equation and you will have 2s = 16. Then divide each side of the equation by 2 and you will have s = 8. Since s = 8 replace s with 8 in your equation. 8 - 4 + 8 + 3 = 15 which is the perimeter. The third side would equal 7.

Answer 2

Answer with Step-by-step explanation:

s represents the length of the second side

The first side of a triangle measures 4 in. less than the second side.

⇒ Length of first side=s-4

The third side is 3 in. more than the first side.

⇒ Length of third side=s-4+3=s-1

⇒ Length of third side=s-1

Perimeter of triangle=15 in.

⇒ s+(s-4)+(s-1)=15

⇒ 3s-5=15

⇒ 3s=20

⇒ s=6.66

⇒ s-1=5.66

Hence, Length of third side=5.66 in.