Oliver had to wash thirty-nine short sleeve shirts and forty-seven long sleeve shirts before school. If he had only washed twenty of them by the time school started, how many did he not wash?

for the points

step-by-step explanation:

step-by-step explanation :

we know that

the measurement of the outer angle is the semi-difference of the arcs which comprises

in this problem

m< xzy is the outer angle

substitute the values

the measure of angle xoy is equal to

> by central angle

substitute the value