McGraw Hill Integrated II, 2012
MH
McGraw Hill Integrated II, 2012 View details
4. Volumes of Prisms and Cylinders
Continue to next subchapter

Exercise 46 Page 837

Use the formula for the lateral area of a cylinder to find a relation between the two radii. Also, use the fact that both cylinders have the same height and the same lateral area.

True

Practice makes perfect
Let's begin by remembering the formula to find the lateral area of a cylinder. L = 2π r h Now, let's considers two cylinders C_1 and C_2 such that they have the same height and lateral area. L_1=L_2 & (I) h_1=h_2 & (II) ⇒ 2π r_1h_1 = 2π r_2h_2 h_1=h_2 Let's substitute Equation (II) into Equation (I) and simplify it.
2π r_1h_1 = 2π r_2h_2 & (I) h_1=h_2 & (II)
2π r_1 h_2 = 2π r_2h_2 h_1=h_2
r_1 = r_2 h_1=h_2
As we can see, we get that the radius of both cylinders is the same. Consequently, the two cylinders have the same dimensions which implies that they have the same volume. So, the given statement is true.