You have the formula for the surface area:
[tex]S = 4 \pi r^{2}[/tex]
where r is the radius.Since radius that is given to you is r = 4x + 1, you need to put 4x + 1 instead of r into this equation:
[tex]S = 4 \pi r^{2} = 4 \pi (4x + 1)^{2} = 4 \pi (16x^{2} + 8x + 1) \\ S= 64 \pi x^{2} + 32 \pi x + 4 \pi [/tex]
This is the answer. Good luck!
