Help please!
options are
10.2
17.6
8.8
13.4

9514 1404 393

  (a)  10.2 ft

Step-by-step explanation:

The total surface area S is the sum of the base area and the lateral area. The base area is the area of the two triangular bases, which have a "base" of 6 ft and a height of 4 ft.

  area of 2 bases = 2(1/2)bh = bh = (6 ft)(4 ft) = 24 ft²

The lateral surface area is the sum of the areas of the three rectangular faces. That will be ...

  total face area = (4 ft)(x) +(6 ft)(x) +(7.2 ft)(x) = (17.2 ft)(x)

So, the total surface area is ...

  200 ft² = 24 ft² + (17.2 ft)(x)

  176 ft² = (17.2 ft)x . . . . . . . . . . subtract 24 ft²

  (176 ft²)/(17.2 ft) = x ≈ 10.2 ft . . . . . divide by the coefficient of x

The unknown prism height is about 10.2 ft.

70

step-by-step explanation:

2*5=10

4*15=60

60+10=

70