Question 74163
First switch the x and y variables
{{{y=2x+1}}}->{{{x=2y+1}}} and then solve for y to find the inverse function
{{{x-1=2y+cross(1-1)}}}
{{{(x-1)/2=(cross(2)y)/cross(2)}}}Divide both sides by 2
{{{y=(1/2)x-(1/2)}}}There's the inverse function. 
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To check this let x=1 and plug it into the original equation
{{{y=2(1)+1}}}
{{{y=2+1}}}
{{{y=3}}}
Take this answer and plug it into the inverse function
{{{y=(1/2)(3)-(1/2)}}}
{{{y=(3/2)-(1/2)}}}
{{{y=(2/2)}}}
{{{y=1}}}
Since you got the number you originally plugged in (which was 1) this shows us that this is the inverse function.