Mathematics OpenStudy (anonymous):

Find the equations of all lines tangent to y = 9–x^2 that pass through the point (1, 12). OpenStudy (anonymous):

gradient of tangent = dy/dx = - 2x = -2 at the point (1,12) using y-y1 = m(x-x1) y - 12 = -2(x-1) y + 2x = 14 is the equation of the tangent OpenStudy (anonymous):

we didn't learn dy/dx.. :( OpenStudy (anonymous):

really? OpenStudy (anonymous):

u sure? OpenStudy (anonymous):

then how would you know the slope of a tangent line, or even what "tangent line" means? OpenStudy (anonymous):

@jimmyrep i don't think this is what the question asks for. it asks for lines tangent to the graph that pass through the point (1,12) OpenStudy (anonymous):

also notice that (1,12) is not on the graph. the slope of a line tangent to the graph of $y=9-x^2$ at a point $(x_1, y_1)$ $-2x_1$ OpenStudy (anonymous):

so you need to solve $-2x_1=\frac{12-(9-x_1^2)}{1-x_1}$ for for $x_1$ OpenStudy (anonymous):

but there is no way to do this without calculus OpenStudy (anonymous):

you get $2x_1(x_1-1)=3+x_1^2$ $x_1^2+2x_1-3=0$ $x_1=-1,x_1=3$ OpenStudy (anonymous):

Where did you get -2x1?.. and how did you set up your equation? OpenStudy (dumbcow):

From taking the derivative of the function: 9-x^2 what class is this for? OpenStudy (anonymous):

Calc lol.. the organization of our book is confusing.. OpenStudy (dumbcow):

oh ok yeah so the slope at any point is -2x then follow satellites steps to find the points where the tangent line goes through (1,12)

Latest Questions solodive: Idk I'm just curious this isn't for class or anything but how do you take care of
52 minutes ago 1 Reply 0 Medals purplecow: The graph shows the functions f(x) PX Angie X pate what is the solution to the pair of equations represented by PX and GX Papi write any two solutions for G
2 hours ago 2 Replies 0 Medals BrokenAngel07: I wrote this some time ago, idk of it'd be considered a song or something I wrote.
3 hours ago 4 Replies 1 Medal Olive2006: Tell me what you think of my story. https://www.wattpad.com/1255046896-unruly-hea
3 hours ago 7 Replies 3 Medals chocalatechipcookie: @vocaloid In circle A, marc BC is 67u00b0 and marc EF is 74u00b0: What is mu2220F
2 hours ago 2 Replies 0 Medals Glyzdl: Question: Given a 60-u00b5C point charge located at the origin, find the total el
17 hours ago 0 Replies 0 Medals Glyzdl: 4) A point charge of 3 nC is located at the point (1, 1, 1) in free space. What c
17 hours ago 0 Replies 0 Medals Sailor: So. I'm gonna send out another plea for help, and I'm desperate at this point. I need to know what I did wrong here.
19 hours ago 7 Replies 3 Medals link1234: what yall think? aye aye aye juice is in wooden box i thought u were gonna shot em first its a different story when ur poppin the percs my demons beatin me
18 hours ago 9 Replies 2 Medals Sailor: Could I get help on this? I know that absolute value should be "6th grade knowledge" but this is Algebra 2 we're talking about.
1 day ago 1 Reply 1 Medal