Question

One angle of the following triangle measures 2x. How many degrees does that angle

Answer 1

Given info:- In triangle (∆)ABC , in which ∠A = 2x, ∠B = x+15° and ∠C = 2x + 10°. Then find the value of x , also find the measure of each angles of a triangle.

Explanation:-

Let the angles be 2x, x+15 and 2x+10 respectively.

∵ Sum of the three angles of a triangle is 180°

∴ ∠A + ∠B + ∠C = 180° [Sum of ∠s of a ∆=180°]

→2x + x+15 + 2x+10 = 180°

→ 2x + x + 2x + 15 + 10 = 180°

→ 3x + 2x + 15 + 10 = 180°

→ 5x + 15 + 10 = 180°

→ 5x + 25 = 180°

→ 5x = 180°-25

→ 5x = 155°

→ x = 155°÷5 = 155/5 = 31.

Now, finding the measure of each angles of a ∆ABC by putting the original value of “x”.

∴ ∠A = 2x = 2(31) = 62°

∠B = x+15 = 31 + 15 = 46°

∠C = 2x + 10 = 2(31) + 10 = 62 + 10 = 72°.