A linear function is a function whose graph is a straight line.
A function is an equation that is a straight line when plotted on a graph.
You cannot, necessarily. Given a graph of the tan function, you could not.
A graph represents a function if and only if every input generates a single output.
If a graph is a function, it will always have y=... or x=... (or anoher letter equals an equation) for example y= 3x-12 is a function
If the function is a straight line equation that passes through the graph once, then that's a function, anything on a graph is a relation!
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You take each equation individually and then, on a graph, show all the points whose coordinates satisfy the equation. The solution to the system of equations (if one exists) consists of the intersection of all the sets of points for each single equation.
You find the equation of a graph by finding an equation with a graph.
The coordinates of the points on the curve represent solutions of the equation.
Any equation where variable a = some multiple of variable b2 + constant will graph a parabola.
The real solutions are the points at which the graph of the function crosses the x-axis. If the graph never crosses the x-axis, then the solutions are imaginary.