Surface area of a square pyramid is the area of the base + 4 times the area of one of the slanted sides.
Area of base = side length * side length
Area of side = (1/2) * side length * slant height
Don't forget that you have to multiply the area of the side by 4!
Step 1: 12 x 12 = 144
Step 2: 12 x 20 = 240 divided by 2 = 120
Step 3: 144 + 120 x 4
This should be quite easy to explain. So the first thing you want to do is multiply them. This isn't to hard if you know your times tables. Don't worry about the decimal till the end.
15.37
× 5
---------
76.85
15.37 times 5 is 76.85
Now on to the decimal. All you need to do is move it two times to the left. You see how it's in between the 5 and 3? The same goes for your answer. So it is 76.85
I hope this helped!! ^^ I can make this a little more easier to explain if you want me to just in case, ok?
The answer is d because 4+8=12 and they are 4 units away from eachother:)
