a surveyor 1standing on a highway observed the angle of elevation of the airplain as 22.5°. at the same time, a surveyor 2 observed the angle of elevation of the same airplane to be 30°. if the airplane was 850m directly above a point on the highway, find the distance between the twi surveyors

Answer 1

There are two different cases here,
you don't say if they are on the same side of the plane, or opposite sides of the plane.
(eg. both looking east , or one looking east the other looking west)

I have them on opposite sides,
horizontal distance from plane of #1
tan22.5 = 750/x1
x1 = 750/tan22.5
similarly
x2 = 750/tan30
distance between = x1 + x2

if they are on the same side, you would take
x1 - x2