00:01
Okay, so i see that you need help with these questions.
00:03
So for question number seven and eight, or i'm sorry, for seven, it shows two triangular prisms.
00:12
And for the first one, it wants you to find the surface, or for both of them, it wants you to find the surface area.
00:24
And so for the first one, i'm gonna take two times three times 11, divide that by two, and then i'm gonna add that to four times five plus nine times four plus 11 times five.
00:41
And because it's made up of three rectangles and two triangles.
00:45
So i'm gonna add 33 plus 20 plus 36 plus 55, and i'm gonna get 144 meters squared.
00:56
That was for the first one.
00:59
For the second one, to get my surface area, my triangle, i have two of them, one on the top and one on the bottom, and they are 24 by 10, and then i'm gonna divide that by two plus your four rectangles that are made up of the lateral sides.
01:16
And so that's 26 times 50 plus 10 times 50 plus 24 times 50.
01:28
Then i'm going to take, i have 240 plus 1300 plus 500 plus 1200, and that is going to equal 4 ,240 meters squared.
01:46
So that's for seven.
01:48
Then for eight, it wants you to find the surface area of the cylinder.
01:52
So to find surface area, the formula is two times pi times the radius squared plus two times pi times the radius times the height.
02:00
And so i'm going to take two times pi times the radius of 2 .5, square that, plus two times pi times 2 .5, which is the radius, times two, because the height is two.
02:17
And so then i'm gonna get 39 .25 plus 31 .4, add those two numbers together, and i'm gonna get 70 .65, and that is in centimeters squared...