Math Is Fun Forum

Kiran

Member

Registered: 2006-11-15

Posts: 177

website choice

for this problem

find the inverse function of y = 7x + 3

can i use this website for help

http://www.analyzemath.com/inversefunction/Tutorials.html

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Live 4 Love

John E. Franklin

Member

Registered: 2005-08-29

Posts: 3,588

Re: website choice

Find where the line intersects y=x diagonal with slope 1 or 45 degree angle line of reflection.
y = 7x + 3
y = x
Subtract these 2 equations.
0 = 6x + 3
x =  -0.5
x = negative a half.
y =  negative a half too at this point if you plug back into an equation.
So if the graph is flipped through the y = x diagonal, then the (-1/2,-1/2) will stay the same.
The slope with change from 7 to 1/7.
y + 1/2 = (x + 1/2) / 7
y = x/7 - 6/14
Yeah!!
Check answer next...
plug in -1/2 for x and see if get -1/2 for y.
Yes you do!!!!
Yeah!!!!!!!!

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igloo myrtilles fourmis

John E. Franklin

Member

Registered: 2005-08-29

Posts: 3,588

Re: website choice

There is an easier way to, just switch y and x and solve for y.
But that's no fun, and what do you learn from that?

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igloo myrtilles fourmis