a ladder leaning against the side of a building makes a 70 degree angle with the ground. if the base of the ladder is 4 feet away from the bottom of the building, approximately how long is the ladder

Respuesta :

Answer:

The ladder is 11,7ft long.

Step-by-step explanation:

This angle can be calculated using the law of cosines:

cos(angle)=opposite cathete/hypothenuse

cos(angle)=ground/ladder

In this exercise we want to calculate the length of the hypotenuse (ladder), so the equation is changed afterwards.

cos(angle)=ground/ladder

cos(angle)*ladder=ground

ladder=ground/cos(angle)

Now the given values are used:

ladder=ground/cos(angle)

ladder=4ft/cos(70°)

ladder=11,7ft

The ladder is 11,7ft long.