A system of equations is good for a problem like this. Let x be the number of student tickets sold Let y be the number of adult tickets sold x + y = 200 2x + 3y = 490 x = 200 - y 2(200 - y) + 3y = 490 400 - 2y + 3y = 490 400 + y = 490 y = 90 The number of adult tickets sold was 90. x + 90 = 200 --> x = 110 2x + 3(90) = 490 --> 2x + 270 = 490 --> 2x = 220 --> x = 110 The number student tickets sold was 110.
angle 1 plus angle 2 equals 90 because they are complementary. combining like terms gives you 8x + 18 = 90. then you get 8x = 72, which means that x equals 9
