The measure of m∠C is approximately 31.6 degrees.
The triangle in the image is a right triangle, with a right angle at ∠B. We know the length of the two legs of the triangle: 18 inches for AC and 12 inches for BC.
We can use the Pythagorean theorem to solve for the length of the hypotenuse, AB.
The Pythagorean theorem states that in a right triangle, the square of the hypotenuse is equal to the sum of the squares of the legs. In this case, we have:
![AB^2 = AC^2 + BC^2](https://img.qammunity.org/2021/formulas/mathematics/high-school/jsgkr5sd23jiqqqltcluoycsuotfr4tjem.png)
![AB^2 = 18^2 + 12^2](https://img.qammunity.org/2021/formulas/mathematics/high-school/pnw6sxo5y8km719mpqb9it58av8xbz2q4t.png)
= 324 + 144
= 468
AB = √468
AB ≈ 21.6 inches
Once we know the length of the hypotenuse, we can use the inverse sine function (
or arcsin) to find the measure of angle ∠C. The sine of an angle is equal to the opposite leg divided by the hypotenuse. In this case, we have:
sin ∠C = BC / AB
sin ∠C = 12 inches / 21.6 inches
∠C =
(12/21.6)
∠C ≈ 31.6°
Therefore, the measure of m∠C is approximately 31.6 degrees.