Which set of numbers could represent the lengths of the sides of a right triangle? A: 8, 9, 10
B: 15, 18, 21
C: 9, 11, 14
D: 7, 24, 25​

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

answer: 1inch=7days  

12inch=12*7=84days

step-by-step explanation: