Down Below is the Picture to the last question.

The value of x is 4

The lengths of the sides of the triangle are 4 ft, 8 ft, and 5 ft

Step-by-step explanation:

The perimeter of the triangle is the sum of the lengths of its three sides

In the given figure

∵ The perimeter of the triangle is 17 feet

∵ The length of its sides are x ft, 2x ft, and 5 ft

∵ P = s1 + s2 + s3

→ Substitute the values of the three sides and the perimeter in the equation

∴ 17 = x + 2x + 5

→ Add the like terms on the right side

∵ 17 = 3x + 5

→ Subtract 5 from both sides

∴ 17 - 5 = 3x + 5 - 5

∴ 12 = 3x

→ Divide both sides by 3 to find x

∵ =

∴ 4 = x

∴ The value of x is 4

→ Use the value of x to find the length of each side

∵ s1 = x

∴ s1 = 4 ft

∵ s2 = 2x

∴ s2 = 2(4)

∴ s2 = 8 ft

∴ The lengths of the sides of the triangle ar 4 ft, 8 ft, and 5 ft