Question

two poles 45m and 30m stand upright on the ground if their feet is 8m apart find the distance between their tops

Answer 1

let ab be the first pole of height 45 m and cd be the second pole of height 30 m

now the distance between their feet is 8m

construction: a line cf parallel to line bd intersecting ab at f is drawn from c
therefore fc = bd

now,
we know that af = ab-cd = 45 - 30 = 15m
In triangle afc
by pythagoreas theorem,
ac^2 = af^2 +fc^2
=> ac = sqrt (af^2 + fc^2)
=> ac = sqrt (15^2 + 8^2) m
=> ac = sqrt (225 + 64) m
=> ac = sqrt (289) m
=> ac = 17 m
therefore the distance between their tops = 17 m