The surface

The surface of a truncated rotating cone with side s = 13 cm is S = 510π cm2. Find the radii of the bases when their difference in lengths is 10cm.

Correct answer:

r1 =  15 cm
r2 =  5 cm

Step-by-step explanation:

s=13 cm S=510π=510 3.14161602.2123 cm2  S = π r12 + π r22 + π (r1+r2) s r1=r2+10   S = π r12 + π (r110)2 + π (r1+(r110)) s S=π x2+π (x10)2+π (x+(x10)) s  1602.2122533308=π x2+π (x10)2+π (x+(x10)) 13 6.2831853071796x218.85x+1696.46=0 6.2831853071796x2+18.85x1696.46=0  a=6.283185;b=18.85;c=1696.46 D=b24ac=18.85246.283185(1696.46)=42991.996771145 D>0  x1,2=2ab±D=12.56637118.85±42992 x1,2=1.5±16.5 x1=15 x2=18  r1,r2>0 r1=x1=15=15 cm

Our quadratic equation calculator calculates it.

r2=r110=1510=5=5 cm   Verifying Solution:  S2=π r12+π r22+π (r1+r2) s=3.1416 152+3.1416 52+3.1416 (15+5) 131602.2123 cm2 S2=S



Did you find an error or inaccuracy? Feel free to write us. Thank you!







Tips for related online calculators
Are you looking for help with calculating roots of a quadratic equation?
Do you have a linear equation or system of equations and are looking for its solution? Or do you have a quadratic equation?

You need to know the following knowledge to solve this word math problem:

Related math problems and questions: