What is the surface area of the triangular prism represented by the net below?

9514 1404 393

  608 cm²

Step-by-step explanation:

The central rectangle is 10+12+10 = 32 cm high and 16 cm wide. Its area is ...

  A = LW = (32 cm)(16 cm) = 512 cm²

Each of the two triangles on the side have an area of ...

  A = 1/2bh = (1/2)(12 cm)(8 cm) = 48 cm²

There are two triangles and one rectangle, so the total surface area is ...

  total area = rectangle area + 2 · triangle area

  total area = 512 cm² +2(48 cm²) = 608 cm²

(b) 240

step-by-step explanation:

first, we use the pythagorean formula using the given side lengths to find x. then we use x to find the side lengths. then we add the side lengths to find the perimeter.

pythagorean theorem formula:

a^2 + b^2 = c^2

(x - 20)^2 + (x - 40)^2 = x^2

x^2 - 40x + 400 + x^2 - 80x + 1600 = x^2

x^2 -120x + 2000 = 0

(x - 100)(x - 20) = 0

x - 100 = 0 or x - 20 = 0

x = 100 or x = 20

we see that the solution x = 20 must be discarded because it will give a negative side length and a side length of 0. the only valid solution is x = 100.

perimeter = sum of the lengths of the sides

perimeter = x + x - 20 + x - 40

perimeter = 3x - 60

replace x with 100.

perimeter = 3(100) - 60

perimeter = 300 - 60

perimeter = 240

answer: the four apples you took away.

step-by-step explanation: