91Ó°ÊÓ

The highest power of the variable in the equation is the degree of the equation.

For a system of equation with highest degree as 1 can have either one solution, no solution or infinite solutions.

For a system of equation with highest degree as 2 can have two solution, no solution or infinite solutions.

For example: Consider system of equations:

Consider the first equation $y=2x+9$.

The equation is in the form $y=mx+c$. Here slope m of the line is 2 and intercept of y-axis c is 9.

Now, consider the second equation $y=x+3$. The equation is in the form $y=mx+c$. Here slope m of the line is 1 and intercept of y-axis c is 3.

Plot the equations on the same plane and the point where both the equations intersect is the solution of the system of the equations.

The red line denotes the equation $y=2x+9$ and blue line denotes the equation $y=x+3$.

Therefore, the point of intersection is $\left(-6,-3\right)$.

Hence, only solution is possible and not two solutions.