document.write( "Question 7666: how do you find the point of intersection when given two y= formulas without graphing? \n" ); document.write( "

Algebra.Com's Answer #4219 by glabow(165) $\"\"$ $\"About$

You can put this solution on YOUR website!
If the y= formulas, as you call them, are y = f(x) (that is to say y in terms of x) you solve the equations to find an y and a x that satisfy both equations simultaneously. That (x, y) set is a point that lies on both lines. That is the intersection.
\n" ); document.write( "The thing to check is whether the two functions are actually two different lines and, if so, whether they are parallel or not. This is why knowing the slope and y-intercept is important.
\n" ); document.write( "If the lines have the same slope but different y-intercepts, they are parallel and there is not solution.
\n" ); document.write( "If the lines have the same slope and the same y-intercept, they coincide and there are an uncountable number of solutions.
\n" ); document.write( "If the lines have different slopes, they intersect and there is one solution. \n" ); document.write( "

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