What's the perimeter of (-9,8) (-9,16) and (-17,8)

16 + sqrt(128)

Step-by-step explanation:

find the lengths of all 3 sides:

the side from (-9,8) to (-9,16) will be 16-8=8 (x stays constant)

The side from (-9,8) to (-17,8) is 8 (-9- (-17)=8)

The side from (-9,16) to (-17,8) will be found from the distance formula

d=sqrt((-17-9)^2 + (8-16)^2))

= sqrt(128)

So the perimeter will be these 3 numbers added together

P=sqrt(128) + 8 + 8

= 16 + sqrt(128)

which can simplify to:

= 16 + 4sqrt(8)

= 16 + 8sqrt(2) = 8+ sqrt(2)

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