Question

ANSWER FAST ILL GIVE BRAINLIEST!!

Answer 1

Given:

A square base pyramid whose base length is 10 in. and height of triangular surface is 4 in.

To find:

The surface area of the pyramid to the nearest whole number.

Solution:

A square base pyramid contains square base with edge 10 in. and 4 congruent triangles with base 10 in. and height 4 in.

Area of a square is

$A_1=(edge)^2$

$A_1=(10)^2$

$A_1=100$

So, area of square base is 100 sq. in.

Area of a triangle is

$A_2=\dfrac{1}{2}\times base\times height$

$A_2=\dfrac{1}{2}\times 10\times 4$

$A_2=20$

So, area of each triangular surface is 20 sq. in.

Now, the total surface area of the pyramid is

Total area = Area of square base + Area of 4 congruent triangles.

$A=A_1+4\times A_2$

$A=100+4\times 20$

$A=100+80$

$A=180$

Therefore, the area of the pyramid is 180 sq. in.