Question

a building 60 feet high. from a distance at point A on the ground, the angle of elevation to the top of the building is 40 degree. from a little nearer at point B, the angle of elevation to the top of the building is 70 degree. What's the distance between point A and B
?

Answer 1

Make your sketch, label the base of the building C
tan40 = 60/AC
AC = 60/tan40

tan 70 = 60/BC
BC = 70/tan70

AB = AC - BC

you do the button-pushing

Answer 2

93.33

Answer 3

49.67

Answer 4

49.7