Answer:21
Step-by-step explanation: plug in 19 and 1
1x3 is 3 plus 19 is 21
<span>D. Regular polygon.
</span>A polygon that has all sides the same measure and all angles the same measure is called Regular polygon.
Hoped I helped!
Angles D and A are equal (from the statement bc the name of triangle starts with A and D)
Now set an equation of the angles so
45 = 5y -10
Add 10 on both sides
55 = 5y
divide by 5
y = 11
Can you add the price of the tickets?