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What is the value of x in a triangle if one angle is 78?

User Jovylle
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1 Answer

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The value of x is 16.

We are given that:

Angle 1 measures 78 degrees: ∠1 = 78°

Angle 3 measures (5x-2) degrees: ∠3 = (5x-2)°

Since vertical angles are congruent, we know that angle 1 and angle 3 are equal in measure. Therefore:

Angle 1 = Angle 3

78 degrees = 5x - 2 degrees

To solve for x, we need to isolate it.

1. Add 2 degrees to both sides:

78 degrees + 2 degrees = 5x - 2 degrees + 2 degrees

80 degrees = 5x

2. Divide both sides by 5:

80 degrees / 5 = 5x / 5

16 = x

Therefore, the value of x is 16.

Complete question:

If the measure of angle 1 is 78 degrees and the measure of angle 3 is (5x-2)degrees, what is the value of x ?

What is the value of x in a triangle if one angle is 78?-example-1
User Ian Bytchek
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