Answer:
b
Step-by-step explanation:
<span>The <u>correct answer</u> is:
576 sq. cm.
Explanation:
The surface area of a figure is the sum of the areas of the faces of the figure.
The slant height goes from the apex of the pyramid along a face and is perpendicular to the base at the bottom of that face. This gives us 2 measurements of each triangular face of the pyramid: the height (the slant height of the pyramid is the height of the triangular face), 18 cm, and the base <span>of the triangular face, 12 cm.
The formula for the area of a triangle is A = 1/2bh; using our measurements we have:
A = 1/2(12)(18) = 108 sq. cm.
There are 4 triangular faces on a square pyramid, and each will have an area of 108 sq. cm.; this gives us:
4(108) = 432 sq. cm.
The area of the base is given by length times width, or 12*12 = 144 sq. cm.
This gives us a total surface area of 432+144=576 sq. cm.</span></span>
Answer:
Sheet metal remaining = 4.1x
cost per square foot of sheet metal = $30
Step-by-step explanation:
Total sheet metal bought = 7.6 ft2
Total sheet metal used = 3.5 ft2
Given equation:
7.6x − 3.5x = 123
Where,
x = cost per square foot
7.6x − 3.5x
Sheet metal remaining = 4.1x
7.6x − 3.5x = 123
4.1x = 123
x = 123 / 4.1
x = $30
Cost per square foot = $30
Z=20
A triangle is equal to 180 degrees so 70+90=160
180-160=20
K÷5-6=74
K= 400
Hope this helps. :):)