The system of equations has infinitely many solutions
Solution:
Given system of equations are:
y = 3x + 12 --------- eqn 1
3y = 9x + 36 ------ eqn 2
We have to find the type of solution
Let us first solve the system of equations by substitution method
Substitute eqn 1 into eqn 2
3(3x + 12) = 9x + 36
9x + 36 = 9x + 36
The equation has infinitely many solutions (in the variable x) if and only if both the overall coefficients of x on the two sides are equal, and the overall constants on the two sides are equal.
Here,
9x + 36 = 9x + 36
Thus the system has infinite solution