Answer:
15
Explanation:
You need to find one of the other angle measures first, I will be solving for the top angle.
To find this you need to take the inverse tangent of the opposite length over the adjacent length, in this case it would be 12 over 9
tan^-1 (12/9)
=53.1. round to the nearest degree so 53
now that you have your angle measure you can take the sine of that angle
for sine you do opposite over hypotenuse, we dont know the length of the hypotenuse so use x
sin(53) = 12/x
0.79 = 12/x don't round the answer to sin(53) wait till the end to round and just use your calculator to remeber the exact number
0.79 = 12/x
•x •x multiply both sides by x
0.79x = 12
/0.79 /0.79 divide both sides by 0.79 this is when you would use the calculator to enter in the exact number not just 0.79
x = 15.02 now you can round to the nearest tenth or whole number for this one it would just be 15
x=15