Answer: Area of Δ DUO = 12.0 square units.
Explanation:
From the diagram, Δ DPA is a right angled triangle and right angled at P.
Therefore ∠D will be
Tan ∅° = PA/DP ie, opposite side all over the adjacent.
= 4.5/3.75
Tan∅° = 1.2
to calculate ∅°, we know find the inverse of Tan 1.2
∅ = Tan^-1 1 .2 from your log tables or calculator
∅° = 50.20°.
= 50°
Since line DR is ⊥ to line OP
∠ADR = 90° - 50°
= 40°.
From the diagram,
∠ADR = ∠UDR = 40°
Therefore,
∠ODU = 180 - ( 40 + 40 + 90 ) { Angle on a straight line }
= 180 - 170
= 10°
From Δ UDM , line MU is he height of the required Δ DUO whose area is to be determined.
Now find the height MU
Tan10.0° = MU/10, where MU is the opposite side and 10.0 is the adjacent from the diagram given.
MU = Tan10.0 x 10.0
= 0.1763 x 10.0
= 1.763
Therefore to calculate the area of Δ DUO
= 1/2 x base x height
= 1/2 x line OD x line MU
= 1/2 x 14.0 x 1.763
= 7 x 1.763
= 12.341
= 12.0 square units.
=