9-2 Area of a triangle

For a right triangle use the formula: A=½bh

For a non-right triangle use the formula: A=½ (adj. leg) (adj. leg) (sin angle between)

Find the area of each triangle.

Ex. 1. a=4, b=5, angle C= 30°

For this problem you would use the formula A=½(adj. leg) (adj. leg) (sin angle between). So, A=½ (4) (5) (sin 30°) would give you the area of 5cm^2.

2. a=4, b=5, angle C=150°

For this problem you would use the formula A=½(adj. leg) (adj. leg) (sin angle between). So, A=½ (4) (5) (sin 150°) would give you the area of 5cm^2.

3. Find the area of triangle XYZ if x=16, y=25, and angle Z=52°.

For this problem you would use the formula A=½(adj. leg) (adj. leg) (sin angle between). So, A=½ (16) (25) (sin 52°) would give you the area of 157.602cm^2.

4. Find the area of triangle RST if angle S=125°, r=6, t=15.

For this problem you would use the formula A=½ (adj. leg) (adj. leg) (sin angle between). So, A=½ (15) (6) (sin 125°) would give you the area of 36.862cm^2.