Find the value of each variable. for the circle, the dot represents the center.

Part 1) The measure of angle d is 65°

Part 2) The measure of angle c is 89°

Part 3) The measure of arc a is 131°

Part 4) The measure of arc b is 47°

Step-by-step explanation:

we know that

In an inscribed quadrilateral, opposite angles are supplementary

step 1

Find the measure of angle d

∠d+115°=180°

∠d=180°-115°=65°

step 2

Find the measure of angle c

∠c+91°=180°

∠c=180°-91°=89°

step 3

Find the measure of arc a

we know that

The inscribed angle measures half that of the arc comprising

115°=(1/2)[99°+arc a]

230°=[99°+arc a]

arc a=230°-99°=131°

step 4

Find the measure of arc b

we know that

The inscribed angle measures half that of the arc comprising

∠c=(1/2)[arc a+arc b]

substitute the values

89°=(1/2)[131°+arc b]

178°=[131°+arc b]

arc b=178°-131°=47°

the 4th choice is the correct one

step-by-step explanation: