please help me :( I need help

Step-by-step explanation:

Lines l and m are the parallel lines and 't' is a transversal line,

Therefore, ∠1 ≅ ∠5 [Corresponding angle postulate]

∠5 ≅ ∠7 [Vertical angles theorem]

∠1 ≅ ∠7 [Transitive property]

Therefore, ∠1 ≅ ∠7 [Alternate exterior angles theorem]

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

i think it would be 42cm