1. in triangle rst, the measure of zr=31° and the measure of zt=57º. find the measure of zs. [a] 147 [b] 121° [c] 88° [d] 920

92°

Step-by-step explanation: In every triangle, there are a total of 180 interior degrees, meaning if we add up two of the three angles, we can calculate how many degrees we are away from the total 180. 31° + 57° = 88°. Subtract the 88° from 180° and we get 92°.

step-by-step explanation:

the multiplicative inverse of a fraction a/b is b/a. for the multiplicative inverse of a real number, divide 1 by the number. for example, the reciprocal of 5 is one fifth 1/5 or 0.2, and the reciprocal of 0.25 is 1 divided by 0.25, or 4.