The sum of four times a number and fifteen is forty-seven. Find the number.

8 is the number

Step-by-step explanation:

I don't know why it took me so long to figure it out, 4 x 8 = 32 32 + 15 = 47

It probably took me a really long time because I am tired, and I am not using a calculator.

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