SOLUTION: Find the area of Triangle ABC, if AB=6cm, AC=12cm, and the measure of angle A is 20 degrees. Express your answer to the nearest tenth of a square centimeter.

Question 442956: Find the area of Triangle ABC, if AB=6cm, AC=12cm, and the measure of angle A is 20 degrees. Express your answer to the nearest tenth of a square centimeter.
Answer by swincher4391(1107) (Show Source): You can put this solution on YOUR website!
We know that angle A is opposite BC.
Let's call side AB and side AC
We can find what cos(A) is since we know A = 20�
Let's use the law of cosines.
Let BC = a, AB = c , AC = b
a^2 = b^2 + c^2 - 2bc cos(20)
a^2 = 12^2 + 6^2 - 2(12)(6)cos(20)
a^2 = 144 + 36 - (144cos(20)
a^2 = 180 - 144*cos(20�)
Use your calculator find cos(20�). Make sure your calculator is in DEGREE MODE and not RADIAN MODE.
a^2 = 180 - 144 * (0.939692621)
a^2 = 44.6842626
a = 6.68462883
We know that (1/2)(a)(b) gives us the area.
We have a and we have b.
(1/2)(6.68462883)(6) = 20.053888565 cm.
cm when rounded.

RELATED QUESTIONS
in right triangle ABC, AB=20, AC=12, BC=16 and angle c is 90 degrees. find to the nearest (answered by Alan3354)

in right triangle ABC, AB=20, AC=12, BC=16, and the measurement of angle c=90 degrees .... (answered by nyc_function)

To the nearest degree, find the measure of angle B in Triangle ABC given measure of Angle (answered by ccs2011)

In the accompanying diagram of right triangle ABC, AB = 5000 and angle C =90 degrees. If... (answered by fractalier)

in the accompanying diagram of Triangle ABC, AB is congruent to AC. The measure of Angle... (answered by edjones)

in the accompanying diagram of Triangle ABC, AB is congruent to AC. The measure of Angle... (answered by KMST,AnlytcPhil)

in a parallelogram ABCD the diagonal AC is at right angle to AB if AB =12CM and BC =13 CM (answered by pallavi)

Triangle ABC is isoceles with ABis equal to AC 7.5cm and BC is 9cm. The height AD from A... (answered by jojo14344)

In a Triangle AC=6cm, AB=5cm and angle(BAC)= 30Deg, Find the area of the... (answered by harpazo)