How do u do algebra because i don't understand

this may not be at all, but i use the same website you're using for school, and if i'm stuck doing one of these i try to look for it on the section.

for this case we have that by definition, the surface area of a cylinder is given by:

where:

r: it is the radius of the cylinder

h: it is the height of the cylinder

we can also rewrite it as:

where:

la: it's the lateral area

ba: area of the base

option a