Question

I need help to answer/ solve this

What is the first step for solving this system of equations using the SUBSTITUTION method?
x - 2y = 8
x = 5 - y

Answer 1

`{x,y}={6,-1}`

Explanation:

Solve by Substitution :

// Solve equation [2] for the variable y

[2] y = -x + 5

// Plug this in for variable y in equation [1]

[1] x - 2•(-x +5) = 8

[1] 3x = 18

// Solve equation [1] for the variable x

[1] 3x = 18

[1] x = 6

// By now we know this much :

x = 6

y = -x+5

// Use the x value to solve for y

y = -(6)+5 = -1

Solution :

`{x,y} = {6,-1}`