Two angles of a quadrilateral measure 308° and 17°. The other two angles are in a ratio of 3:4. What are the measures of those two angles?

1 answer

Let's call the two unknown angles x and y. We know that:

- x:y is in a ratio of 3:4, so we can write x = 3a and y = 4a for some value of a.
- The sum of the angles in a quadrilateral is 360°, so we can write an equation:

308° + 17° + x + y = 360°

Substituting in our expressions for x and y, we get:

308° + 17° + 3a + 4a = 360°

Simplifying the left side:

325° + 7a = 360°

Subtracting 325° from both sides:

7a = 35°

Dividing by 7:

a = 5°

So x = 3a = 15° and y = 4a = 20°. Therefore, the two unknown angles are 15° and 20°.