There are 90 seats in the school auditorium. The school had a sold out show of their play last weekend, and made $315. The cost of a ticket for an adult was $5.00 and the cost of a ticket for a child is $2.50. Which system of equations could be used to determine the number of adults, a, and
the number of children, c, that attended the showing of the movie?

63 seat for adults and 27 seat for children.

please mark me as brainliest

second option

step-by-step explanation:

the measures of a triangle equal 180. use that to find x.

2x+3x+4x=180

9x=180

9x/9=180/9

x=20

now you know x, you know angle a is 40°, angle b is 60°, angle c is 80°.

because angle a is 40°, the first option doesn't work.

because angle b is 60°, the second option does work.

when you add angle a and b, you get 100°. complementary means it equals 90°, so the third option doesn't work.

when you add angle a and c, you get 120°, which is not 100.