Question

A girl flies a kite at a height of 300 ft, the wind carrying the kite horizontally away from her at a rate of 4 ft/sec. How fast must she let out the string when the kite is 428 ft away from her?

On a problem like this would I differentiate

a^2+b^2=c^2

or a^2+300=c^2?

Because the 300 seems to be a constant. Just making sure for my test.

Answer 1

a^2+300^2=c^2? ***

Answer 2

or a^2+300=c^2
careful, square the 300 too.

Answer 3

Yeah caught that too hahah