The triangle on the left is just an enlargement of the smaller triangle or you can say the smaller triangle is a reduction of the bigger one, but they share the same angle measures
If there are 20 rows each and 15 per row then you would multiply 20(15) = 300 then so there are 300 seats in Section J. each seat is 18$ so you would multiply 300(18) = 5400 so section J would get 5,400$ if it were to be sold out. The equation is 20(15)=300(18)=5400
