172.9
You find it by multiplying each side of the triangle by the height (9) and adding the results together.
A(lateral) = 8 * 9.1 + 3 * 9.1 + 8 * 9.1
= 72.8 + 27.3 + 72.8
= 172.9
Answer:
x + 61 = 411
Step-by-step explanation:
Let x = the number of adult tickets sold
Let x + 61 = the number of student tickets sold
x + x + 61 = 761
2x = 700
x = 350