50 POINTS! This figure is a tetrahedron. What is its surface area?

124.8 square units

249.6 square units

187.2 square units

312 square units

249.6 square units

Step-by-step explanation:

The surface area of a tetrahedron consists of 4 times the same areas. So we just need to get the area a of the triangle with the given height h = 10.4 and base length b = 12 which is . Multiply with 4 to get the whole thing.

x=17

step-by-step explanation:

solve 3x-24=x+10

then that makes it 2x=34 because you subtract an x from both sides to get rid of the one on the right, and then you add 24 to both sides to get rid of the 24 on the left

divide by both sides by 2 to get your answer so that you can get your answer

56.6

step-by-step explanation:

the ratio of the perimeters is equal to the scale.

the ratio of the areas is equal to the square of the scale.

34 / 20 = k

a / 19.6 = k²

substituting:

a / 19.6 = (34 / 20)²

a = 19.6 (34 / 20)²

a ≈ 56.6