The surface area of a cylinder is 972xPi and the diameter of the top circle is 2x and the length is 5x..... solve for x.....tf how do you do this question..
-the answer is 9 i just don't know how to do the question
+128475 Surface area of a cylinder = 2pi r^2 + 2pi r h
If the diameter = 2x......then the radius = x
So we have this
972 pi = 2pi *x^2 + 2pi * x * 5x divide out pi and simplify
972 = 2x^2 + 10x^2 divide through by 2
486 = x^2 + 5x^2
486 = 6x^2 divide both sides by 6
81 = x^2 take the positive root of both sides
9 = x
