>>16759730
math concepts build on each other, number of solutions to an equation leads into number of solutions to a system of equations, which will tell you the exact point they intersect, or if they have no solutions and are parallel to each other. or if they have infinite solutions they're the same line.

you'll get questions like
Town A's population is x and increases by y each year
Town B's population is w and increases by z each year
in how many years will town B's population be greater than town A's
and instead of exhaustively inputting years to see which one fits you can just set them equal to each other x+yt=w+zt where t is your years, and [math]\frac{x-w}{z-y}=t[/math] is your answer

and this leads into more complex problems involving quadratics, and higher degree polynomials.