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Find the value of each of the lettered angles in the diagram below​

Find the value of each of the lettered angles in the diagram below​-example-1
User Ross Lote
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1 Answer

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Answer:

Explanation:

Remark

You have an isosceles triangle. That means that the angles opposite the marked sides are equal. So mark the angle on the lower left of the triangle as 50 degrees.

The solution to problem depends on the fact that the sum of the two inside angles of the triangle (each of which is marked as 50 degrees) not supplementary to the exterior angle, are still equal to the exterior angle.

Givens

<1 = 50 degrees

<2 = 50 degrees

Exterior angle = 15x + 25 Substitute the givens into the equation

Equation

<1 + <2 = 15x + 25

Solution

50 + 50 = 15x + 25 Combine the left side

100 = 15x + 25 Subtract 25 from both sides

100 - 25 = 15x + 25 - 25 Combine

75 = 15x Divide both sides by 15

75/15 = 15x/15

5 = x

Answer

<1 = 50 degrees

<2 = 50 degrees

15x + 25 = 75 + 25 = 100