SOLUTION: MAY I PLEASE GET SOME HELP WITH THESE I REALLY NEED HELP A regular squre pryramid with slant height 9 and base edge 6 (a)lateral area (b)the total area A right cylinder wit

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Question 86784: MAY I PLEASE GET SOME HELP WITH THESE I REALLY NEED HELP
A regular squre pryramid with slant height 9 and base edge 6
(a)lateral area
(b)the total area
A right cylinder with radius 3 and height 7
(a)lateral area
(b) the total area
Two circles have area of 49pi and 36pi. Find the ratio of their radii.
Answer by Flake(45) (Show Source):
You can put this solution on YOUR website!
You need to understand the terms "lateral Area" and "Total Area". Once understand that, it should be pretty straight forward.
A regular squre pryramid with slant height 9 and base edge 6
a) Lateral Area for regular pryramid = 1/2*(perimeter of the base)*(slant height)
-----slant height is given, you need to find the perimeter for the square base
b) the total area = lateral area + base area
----- you know the lateral area from "a". You should know the area for a square base
------------------------
A right cylinder with radius 3 and height 7
a) Lateral Area = (height) * (circumference of the base)
---------- height is given. The circumference of a cone is a circle. You need to calculate the circumference of a circle whose radius is 3
b) the total area = lateral area + base areas
----- you know the lateral area from "a". You should how to calculate the area of a circle base.
------ remember a cone has 2 circle bases. One on the bottom the other is the top.
---------------
Two circles have area of 49pi and 36pi. Find the ratio of their radii.
Let R#1 be radius#1.
Let R#2 be radius#2.
Radio = R#1/R#2
---Find R#1: Area of circle=(pi)(R^2)
So 49pi=(pi)(R#1^2)
So 49=R#1^2
So R#1 = sqrt of 49
-----Now repeat to find R#2 and find ratio