Question

construct a equilateral triangle whose altitude is 3.5 cm

Answer 1

Draw a line XY. Take any point D on this line. Construct perpendicular PD

on XY. Cut a line segment AD from D equal to 3.5 cm.
Make angles
equal to 30° at A
on both sides of
AD, say ∠CAD
and ∠BAD where
B and C lie on XY.
Then ABC is the
required triangle.
Justification
Since ∠A = 30° +
30° = 60° and
AD ⊥BC, ΔABC
is an equilateral
triangle with
altitude AD =
3.5 cm.