Find the total surface area of this triangular prism.

The surface area of the prism is 144cm²

Step-by-step explanation:

First of all we need to calculate the area of the triangle

a = area of triangle

a = (8 cm * 6 cm) / 2

a = 48cm² / 2

a = 24cm²

Now we have to calculate the 3 areas of the rectangles

a1 = 4cm * 10cm

a1 = 40cm²

a2 = 4cm * 8cm

a2 = 32cm²

a3 = 4cm *6cm

a3 = 24cm²

Now we must add all the calculated areas and the triangle 2 times

a1 + a2 + a3 + 2a =

40cm² + 32cm² + 24cm² + 2 * 24cm²

144cm²

The surface area of the prism is 144cm²

c.

step-by-step explanation:

because first you have to add the 4x, 9x, and the 7x together and you get 20x and then you add the last numbers up and you get 5and then you put the subtraction sign in there and that's how you get the answer.