# Tangent to a curve that passes through a given point

• Aug 18th 2009, 01:41 AM
jebusdood
Tangent to a curve that passes through a given point
y = -3.39x2 + 3.21x Determine the positions on the curve (x,y), of all tangents that pass through the point (-4.87,67.22). Enter none if no tangent exists. ENTER THE LEFT-MOST TANGENT POINT (the one with the lowest x-value) IN THE FIRST BOX!
Round all values to FOUR decimal places, using the normal convention. Pad with zeros if necessary.
Example1: (-0.2305,2.3670)

Left-most tangent point (x,y) = [correct answer is (-11.8095,-510.6958)]
Right-most tangent point (x,y) = [correct answer is (2.0695,-7.8761)]

I've tried the approach you've listed here (http://www.mathhelpforum.com/math-he...tml#post351621) and it just doesn't seem to work for me. I was wondering if you could post a step by step approach so i can understand the process a little bit better.

Thank you

Billy
• Aug 18th 2009, 02:36 AM
missb
Quote:

Originally Posted by jebusdood
y = -3.39x2 + 3.21x Determine the positions on the curve (x,y), of all tangents that pass through the point (-4.87,67.22). Enter none if no tangent exists. ENTER THE LEFT-MOST TANGENT POINT (the one with the lowest x-value) IN THE FIRST BOX!
Round all values to FOUR decimal places, using the normal convention. Pad with zeros if necessary.
Example1: (-0.2305,2.3670)

Left-most tangent point (x,y) = [correct answer is (-11.8095,-510.6958)]
Right-most tangent point (x,y) = [correct answer is (2.0695,-7.8761)]

I've tried the approach you've listed here and it just doesn't seem to work for me. I was wondering if you could post a step by step approach so i can understand the process a little bit better.

Thank you

Billy

Hey Billy,

You are obviously in my Calc course at USC atm!!

I am still having drama's with this question too :(

I drew a picture, and sort other idea's but still no luck.

Miss B
• Aug 18th 2009, 05:55 AM
mr fantastic
Quote:

Originally Posted by jebusdood
y = -3.39x2 + 3.21x Determine the positions on the curve (x,y), of all tangents that pass through the point (-4.87,67.22). Enter none if no tangent exists. ENTER THE LEFT-MOST TANGENT POINT (the one with the lowest x-value) IN THE FIRST BOX!
Round all values to FOUR decimal places, using the normal convention. Pad with zeros if necessary.
Example1: (-0.2305,2.3670)
Left-most tangent point (x,y) = [correct answer is (-11.8095,-510.6958)]
Right-most tangent point (x,y) = [correct answer is (2.0695,-7.8761)]

I've tried the approach you've listed here (http://www.mathhelpforum.com/math-he...tml#post351621) and it just doesn't seem to work for me. I was wondering if you could post a step by step approach so i can understand the process a little bit better.

Thank you

Billy

Please show what you've done and where you get stuck. A way of solving this sort of question is given in the link.