Question

Solve the system of eqaution.y=-4x+15,y=-7/2x+12

Answer 1

{y,x} = {-9,6}

Explanation:

[1] y + 4x = 15

[2] y + 7x/2 = 12

// To remove fractions, multiply equations by their respective LCD

Multiply equation [2] by 2

// Equations now take the shape:

[1] y + 4x = 15

[2] 2y + 7x = 24

Next

// Solve equation [1] for the variable y

[1] y = -4x + 15

// Plug this in for variable y in equation [2]

[2] 2•(-4x+15) + 7x = 24

[2] - x = -6

// Solve equation [2] for the variable x

[2] x = 6

// By now we know this much :

y = -4x+15

x = 6

// Use the x value to solve for y

y = -4(6)+15 = -9

Solution :

{y,x} = {-9,6}