HELP!!
9. What is the area of triangle AOB?
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Angles ∠ACD and ∠CAB are congruent because they are alternate angles. Then the area of the triangle AOB will be 22.53 square cm.
The area of the right-angle triangle is given as
A = 1/2 x B x H
Where B is the base and H is the height of the right triangle.
We know that angles ∠ACD and ∠CAB are congruent because they are alternate angles.
α₁ = 40°
AO = OC = 7.8 cm
Then the area of the triangle will be
Area = 1/2 x 7.8 x 7.8 x tan40°
Area = 22.53 square cm
More about the area of the right-angle triangle link is given below.
https://brainly.com/question/16653962
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