This is a simple quadratic function.
To solve x or y, we need to put the coefficient of x or y same for each equation so that x or y can be eliminated when we subtract or add the two equations.
Let's eliminate y.
The coefficient of y in the first equation is 1, and in the second equation, it is -4. Therefore, if we multiply 4 to the first equation, the coefficients of ys in the both equation will be same.
==> 8x +4y= 36
Now, let's add both the equation.
18x = 72
x=72/18 = 4
Now, let's solve y.
Substitute x for 4. Then, the first equation is
2(4) + y=9
Therefore, x=4, y=1.
Let's check if these two values are correct.
If we substitute these values in the second equation,
Since the equation is correct, x=4 and y=1.