Question

Y = x - 1

x + 4y = 16
Im having troubles. Can some 1 explain in complete explanations and all expressions.

Answer 1

{x,y} = {4, -3}

Substitution :

// Solve equation [2] for the variable x

[2] x = 4y + 16

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

[1] (4y+16) + y = 1

[1] 5y = -15

// Solve equation [1] for the variable y

[1] 5y = - 15

[1] y = - 3

// By now we know this much :

x = 4y+16

y = -3

// Use the y value to solve for x

x = 4(-3)+16 = 4