A rectangular barn door needs to be painted. The door is 81 inches high and 50 inches wide. What is the area of the front of the door?
А
8,100 square inches
B
1,620 square inches
524 square inches
D 4,050 square inches

D. 4050

If you multiply the height and width you get the area.

Hey! So you could use your calculator or do it by hand. You are trying to find the sin of this equation because it involve the hypotenuse and the opposite side.
So it would be the sin(60) = 7/x       (x is the hypotenuse, it is sin(theta) = opposite over hypotenuse)
Which is simplified to x = 7 / sin(60)
Now you could do this by hand because the sin(60) is the square root of 3 over 2 and so it would be x = 7 / square root of 3 over 2. 
So you would do 7/1 times 2/square root of 3
then it would simplify to 14/square root of 3 
which would simplify to 14 times square root of 3 / 3 which is 8.08 rounded
hope this helps!