Question

How do you find the measure of angle A?

Answer 1

m∠A = 18

Explanation:

Formula:

the sum of the interior angles of a triangle is 180.

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According to the formula :

`m\angle A\ +\ m\angle B\ +\ m\angle C=180`

⇔ x - 22 + 3x + 19 + x - 17 = 180

⇔ 5x + (19 - 17 - 22) = 180

⇔ 5x + (2 - 22) = 180

⇔ 5x - 20 = 180

⇔ 5x = 180 + 20

⇔ 5x = 200

`\Leftrightarrow x = (200)/(5) \\\Leftrightarrow x = 40`

Conclusion:

m∠A = x - 22 = 40 - 22 = 18