Algebra-1

To solve the given system of equations using the elimination method, we can subtract the first equation from the second equation to eliminate the variable "x". Let's perform the subtraction:

(x + 7y) - (x + 4y) = -12 - (-3)

Simplifying the equation, we have:

x - x + 7y - 4y = -12 + 3

The x terms cancel out (x - x = 0), and the y terms combine:

3y = -9

To solve for y, we divide both sides of the equation by 3:

3y / 3 = -9 / 3

y = -3