i have to use pythagorean theorem to find the leg-measure of x. in the formula, x would be a^2. the hypotenuse is 11 and "b" is unknown. there is also a cosine with a measure of .4 at the top-most angle.. what is x? i don't know how to use cosine with the problem

1 answer

Using the topmost angle, the cosine is

adjacent/hypotenuse

so .4 = b/11, making b=4.4

Now, with c=11,b=4.4, that means that
a^2 = 11^2 - 4.4^2 = 101.64, so
a = 10.1