I need help with this math problem please

Question

A ladder is placed 6 ft from the base of a building at an angle of 70° with the ground. How long is the ladder?

Answer 1

6/cos70 =6sec70 = about 17.54 feet long ladder

cosine of an angle = adjacent side over hypotenuse

hypotenuse = the ladder length

adjacent side = distance from the bottom of the ladder to the wall