Which formula is used to find the area of a triangle when two sides and the included angle are known (SAS case)?

A triangle ABC has sides $a$ and $b$ with included angle $C$. If a sector of a circle with radius $r$ and central angle $C$ is drawn such that the triangle is inscribed within the sector and the region outside the triangle but inside the sector is shaded, what is the area of the sector that is not shaded?

What is the sum of the interior angles of a $pentagon$?

Given triangle QRS with sides $q$ and $r$ enclosing angle $S$, what is the formula for the area of triangle QRS?

Which triangle's area can be calculated using the trigonometric area formula $A=\frac{1}{2}absinC$?

Given triangle DEF with sides $d$ and $e$ and included angle $F$, what is the formula for its area?

Given a triangle with an included angle of $30°$ and a side of length $7$ feet adjacent to the angle, if the area of the triangle is $12.6$ square feet, what is the length of the base adjacent to the angle?

Given a circle with a radius of $12$ units and a central angle of $120°$, what is the area of the sector that is not shaded if the shaded sector corresponds to the given central angle? Choose the closest value.

Given that the measure of central angle $\mathrm{QRS}$ is $\theta$ radians in a circle of radius $r$, what is the area of the shaded sector? Choose the correct formula from the options below.