If the radius of a sphere is increased by 5 cm so that the area of the sphere obtained is increased by 400pi square cm. what was the radius before the increase

The answer is 314cm²

the formula for the sphere area of a sphere is:

A= 4TT²

A = 4x3.14x5²

first solve for exponents

A = 4x 3.14x25

then multiply

A = 314cm²

the least common denominatore of 7 and 2 is 9

step-by-step explanation:

7+2=9

18

step-by-step explanation:

draw the shape and you will see that f and k are actually at adjacent vertices (points of the hexagon that are neighboring).   so find the distance between (1,2) and (4,2).   that is easy since (1,2) and (4,2) is just a vertical distance to count, which is 3.   it is a regular polygon which means all sides are congruent.   you have 6 sides (hexa) so multiply 6 by 3 to receive 18.