algebra
posted by peg .
How many solutions does the following system have:
6x  3y = 9
2x  y = 3
Explain how to determine the number of solutions without solving the system. Then apply elimination, and interpret the resulting equation.
could you please explain this to me?

number of solutions:no more than the degree of the equation.
In the above, both x,y are degree one, so there is at most one real solution. THere maybe no solutions.
To solve, multiply the lower equation by 3, and you see that they are the same equation, which then has no solution, as the two lines are colinear (the same). It takes graphs that cross each other (intersect) to produce a solution.