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(Using algebra)
Find the measure of Please help!!!

(Using algebra) Find the measure of Please help!!!-example-1

2 Answers

4 votes

angle

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The sum of the angles in a triangle is 180°. We have an equilateral triangle with side angles of 30°. By using algebra, we get :

∠A + ∠B + ∠C = 180°

x° + 30° + 30° = 180°

x° + 60° = 180°

x° = 180° - 60°

x° = 120°

Conlude : The measure of x is 120°

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User Prophet
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We are given that sides AB and AC are congruent. By the Isosceles Triangle Theorem, the base angles opposite those sides are also congruent. One base angle measures 30,° which means that angle ACB must also measure 30.° This is possible by the Isosceles Triangle Theorem. Additionally, we can apply the Triangle Sum Theorem, which states that all three interior angles of a triangle must sum up to 180.°

Let’s create an equation to solve for “x:”

2(30)+x=180

We know that the two base angles measure 30,° so 30+30=2(30).

Solve for “x:”

Multiply the 2:

60+x=180

Subtract 60 from both sides:

x=180-60

x=120

Therefore, x=120°
User Doto Pototo
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