Find the surface area of a right cylinder with a height of 8 in and a base radius of 5in.?

SA= 2 π r2 + 2 π r h

SA= 2(3.14) (5in)^2 + 2(3.14) (5 in) (8 in)

SA= 157 in^2 + 251.2 in^2

SA= 408.2 in^2

surface area = 2*base area + wall area

base area = pi*r^2 = pi*5^2 = 25 pi

2* base area = 50 pi

circunference = 2*pi*r = 2*pi*5 = 10 pi

wall area = circumference * height

wall area = 10 pi * 8 = 80 pi

50 pi + 80 pi = 130 pi <===== answer (square inches)

if you call pi = 355 / 113

130 pi = approx = 408.41...

pi*r^2 = the surface area of a circle

and for the cylinder part, its base times width

so

2*pi*r*hight

therefore it will be

pi*r^2*2 + 2*pi*r*height

= 408.4in

surface area - 2 x pi x r^2 + 2 x pi x r x h

Gives (using calculator)

130 x pi

= 408.41 square inches correct to 2 decimal places

= 4 * 22/7 * 8 * 5²

= 704/7 * 25

= 17,600/7

= 2,514 2/7

Answer: 2,514 2/7 sq inches OR 2,514.2857 1/7 sq inches