Aprism has isosceles triangle bases with leg lengths of 5 inches, 5 inches, and 8 inches, and a height of 3 inches. the distance between the bases is 12 inches. find the surface area. show your work, . you in advance for assisting me with this math problem

The total surface area is the sum of the lateral area and the area of the bases.

The area of each triangular base is
  A = (1/2)bh
  A = (1/2)(8 in)(3 in) = 12 in²

The lateral area is the product of the perimeter of the base and the distance between bases.
  A = Ph
  A = (5 in +5 in +8 in)(12 in) = 216 in²

Then the total area is
  2*base area + lateral area
  = 2(12 in²) +(216 in²)
  = 240 in²

The surface area of the prism is 240 in².

C. i believe it is (5×(-20))+(100×(0.7))