Make x the subject of the formula. Is this correct?

If this is incorrect could you please tell me the correct answer.

r = 78539458390583095803458309458039485093485 or just 3

step-by-step explanation:

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

both triangles are similar because 2 is just smaller than the big one 1 is similar because they are facing different way's but are similar to each other

step-by-step explanation: