I'm not good at graphing, but desmos.com is an online graphing calculator that works really well.
Answer:
5.36
Step-by-step explanation:
Given that:
<BAD = <CAE, therefore, BD = EC
Let's take x to be the length of BD = EC
BD + DE + EC = BC
BC = 20,
BD = EC = x
DE ≈ 9.28
Thus,
x + 9.28 + x = 20
x + x + 9.28 = 20
2x + 9.28 = 20
Subtract 9.28 from both sides
2x + 9.28 - 9.28 = 20 - 9.28
2x = 10.72
Divided both sides by 2 to solve for x



BD ≈ 5.36
Answer:
To find the lateral surface area, we will find half of the perimeter of the base and multiply it by the slant height of the side triangles. Each triangle has a slant height. The slant height is the height of each triangle, not the height of the pyramid.
Step-by-step explanation: