What expression is equal to COS B?

A/C

Step-by-step explanation:

Since the sum of the angles in a triangle equals 180°, and angle C is 90°.

That means angles A and B add up to 90°, that is, they are complementary angles. Therefore the cosine of B equals the sine of A.

We saw on the last page that sin A was the opposite side over the hypotenuse, that is, a/c. Hence, cos B equals a/c.

Your welcome! :)

irrational, then, just means all the numbers that aren't rational. every integer is a rational number, since each integer n can be written in the form n/1. however, numbers like 1/2, 45454737/2424242, and -3/7 are also rational, since they are fractions whose numerator and denominator are integers.

step-by-step explanation: