Question

From point A and B on level ground, the angles of

elevation of the top of a building
Are 25 degree and 37degrees respectively
1f AB= 57m calculate to the nearest metre the distance of the top building from A and B if they are both on the same side of
the building

Answer 1

Explanation:

Call T the top

call G the bottom

T G B is a right triangle

37 at B, 90 at G, thus 53 at BTG

TGA is a right triangle

25 at A, 90 at G, thus 65 at ATG

thus 122 at ABT

law of sines:

sin 25 / BT = sin 12/ 57

so BT = 156 meters (first answer)

now angle ABT = 180 - 12 - 25

= 143

so

sin 143 /AT = sin12/57

AT = 164 meters, second answer