Need help plzzz???!?!

137

Step-by-step explanation:

First start with what you know.  The measure of the interior angles of a triangle total to so 51 + 2x + x = 180, then 51 + 3x = 180, 3x = 129, so

x = 43, the exterior angle is on a straight line with x so

x + exterior angle = 180 [since they are supplementary], since x = 43 then

43 + e = 180, so e has to be 137

the answer is:

the lateral area is equal to

to find the lateral area of the square pyramid, first we need to find the perimeter of the base, and then, find the lateral area using the following formulas:

where,

s, is the base length

slant height, is the height of a the side of the pyramid

we are given:

now, calculating the perimeter of the base, we have:

then, calculating the lateral area:

hence, we have that the lateral area is equal to

have a nice day!