How do you find the surface area of this triangular prism?

Find the area of the 2 triangle faces first and then find the area of the 3 rectangle faces and add them together to get

Step 1: Find the surface area of the 2 triangles

x2 =

Step 2: Find the surface area of the 3 rectangles

(6x7) x 3 =

Step 3: Add the 2 surface areas together

+ =

Therefore the surface area of the prism is

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