The ratio of males to total students in a mathematics class is 12 to 30. What percent of the class is female? 40%
60%
30%
12%

40%

Step-by-step explanation:

12 divided by 30 is .40 so 40 percent

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18