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$$y = ax^2 + bx + c$$

which is tangent at the origin with the line $y=x$, It is also tangential with the line $y=2x + 3$. Determine the function! Draw a figure!

My main question is this solvable? I am doubtful?

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    What have you tried to do? Can you turn the two conditions on the function $y = ax^2 + bx + c$ into conditions on $a,b,c$? The first condition determines $b$ and $c$. Now you only have $a$ left to figure out, and for that you'll need the second condition.2011-05-21
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    Yes, I've got b and c. b = 1 and c = 0 a = pain in my ass? We need a second condition to solve it right?2011-05-21
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    @aka: It is solvable, using tools that you possess.2011-05-21
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    How? so far I got the function: y = ax^2 + x and we know that it tangetial with the line y = 2x + 3, thus in which point we dont know. So if i put these to against eachother ax^2 + x = 2x + 3 we get: a = (3/ X^2-x) So our function becomes y = (3x^2)/(x^2-x) + x Is this right?2011-05-21
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    Many thanks for your help, Américo and Chandru.... I got it right know! Had even forgotten the equation of tangential! Once again thank you!2011-05-21
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    @aka: please do not use answers to leave comments.2011-05-21
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    @aka: Please accept an answer, so that the question is not in the unanswered list.2011-05-23

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