you know that the interior angles of a triangle equal 180°. so lets find the remaining angle measure
64 + 27 = 91
180 - 91 = 89
so 89 is the third interior angle of the triangle. now let's find the exterior angle.
you know that the extended angle is supplementary; which means it will equal 180° as well. so lets add the third interior angle we just found and let's add it to the unknown expression:
89 + <u>97 + x</u> = 180
186 + x = 180
-186 -186
x = -6
now it might seem wrong because x is negative and it feels like it should be positive. but let's check our answer.
First you have to find out the cost of the ticket. To do so you have to Divide 15 and 6. Which equals $2.50. So each ticket is $2.50 dollars. Now you have to multiple 2.50 times 9. which equals 22.5. So your total answer is $22.50 dollars
