What is the substitution of -6x-8y=-20 and x+6y=-6

Substitution doesn't work for this, but elimination does.

-6x-8y=-20 +6( x+6y=-6)

-6x-8y=-20 + 6x+36y=-36

-6x and 6x cancel each other, add -8 and 36 to get 28, and -20 and -36 to get -56.

28y=-56

divide by 28 on both sides.

Y= -2

Then substitute y into one of the equations.

x+6(-2)=-6

x-12=-6

x=6

The ordered pair is (6,-2).

x=-4/3y+10/3 and x=-6-6y

Option B, c =

Step-by-step explanation:

Use Pythagorean Theorem:  a^2 + b^2 = c^2

Step 1:  Plug in

(3)^2 + (15)^2 = c^2

9 + 225 = c^2

sqrt(234) = sqrt(c^2)

c =

 Option B, c =