Please help me thank you!!

sqrt 7

Step-by-step explanation:

The formula is a^2+b^2=c^2, where a and b are the "legs" of the traingle, and c is the "longest" side of the traingle. In this case its:

3^2+b^2=4^2

=9+b^2=16

=b^2=7

=sqrt 7

-2

7 - 9 = -2

reversed:

-2 + 9 = 7

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