In a tiangle ABC, the measure of angle B is two-third of the measure of angle A.The measure of angle C is 20 degree more than the measure of angle A.find the measure of three angles
Answers
Answer:
\angle A=60^{\circ}∠A=60
∘
, \angle B=40^{\circ}∠B=40
∘
, and \angle C=80^{\circ}∠C=80
∘
Explanation:
Given: In triangle ABC the measure of angle B is two - third of the measure of angle A. The measure of angle C is 20 degree more than the measure of angle A
To find: Measure of the three angles
Solution:
Let the measure of angle A be x^{\circ}x
∘
. So, measure of angle B is \frac{2}{3}x^{\circ}
3
2
x
∘
, and measure of angle C is (x+20)^{\circ}(x+20)
∘
Now, we know that
\angle A+\angle B+\angle C=180^{\circ}∠A+∠B+∠C=180
∘
[Angle sum property]
x+\frac{2}{3}x+x+20=180^{\circ}x+
3
2
x+x+20=180
∘
2x+\frac{2}{3}x+20=180^{\circ}2x+
3
2
x+20=180
∘
2x+\frac{2}{3}x=160^{\circ}2x+
3
2
x=160
∘
8x=480^{\circ}8x=480
∘
x=60^{\circ}x=60
∘
So, \angle A=60^{\circ}∠A=60
∘
, \angle B=\frac{2}{3}\times60^{\circ}=40^{\circ}∠B=
3
2
×60
∘
=40
∘
, and \angle C=(60+20)^{\circ}=80^{\circ}∠C=(60+20)
∘
=80
∘
Wish this hepled you..