Question

Can someone please explain to me how to do 7,8,and 9 on this Proof? Document in comments.

Answer 1

You don't need to say the answer, just explain how I get the answer, cuz I'm so lost!

Answer 2

@terenzreignz

Answer 3

Do you use calculus here?

Answer 4

nope, geometry

Answer 5

Honestly, if I were faced with such a test, I wouldn't be able to answer it quickly like you did :)

However, your answers to the previous questions should suffice, you need the equation of the line tangent to the circle and through the point (5,6)

You know its slope is -3/4

So you have a slope and a point.

The point-slope form of a circle, if you have the slope m, and a point (a,b) goes as follows...
\[\Large y = \color{green}m(x-\color{red}a)+\color{blue}b\]

Answer 6

:)
But what about the x-intercept> is it just 5>

Answer 7

*? *?

Answer 8

First, what's the equation?

Answer 9

y = mx +b

Answer 10

Yeah, but specifically, what's the equation for the line tangent to the circle at the point (5,6) ?

Answer 11

uhhhh...

Answer 12

do you mean the equation of the circle?

Answer 13

wait nevermind

Answer 14

i don't know... :(

Answer 15

(x – 2)^2 + (y – 2)^2 = 5^2 is that it?

Answer 16

NO, the equation of the line tangent to the circle at the point (5,6)

You know that its slope is -3/4
and it passes through the point (5,6)

So you have a slope and a point.

The point-slope form of a circle, if you have the slope m, and a point (a,b) goes as follows...

\[\Large y = \color{green}m(x-\color{red}a)+\color{blue}b\]

Answer 17

so, the equation is y = m(x-a) + b?

Answer 18

y = -3/4 (x - 5) + 6

Answer 19

That's right :)
Now simplify it.

Answer 20

but how do i find two variables in one equation?

Answer 21

No, I just meant simplify, like distribute that -3/4 and then combine like terms...

Answer 22

okay

Answer 23

y = -3/4x + 3 3/4 + 6
y = -3/4 + 9 3/4

Answer 24

like that?

Answer 25

*y = -3/4x + 9 3/4

Answer 26

I suppose :)

Now to find the x-intercept, set y = 0 and then solve for x :)

Answer 27

okay:
0 = -3/4x + 9 3/4
-9 3/4 = -3/4x
13 = x

Answer 28

Sorry, I'm a little lost on dividing mixed-number fractions... (how are you doing that?!)
Give me a minute...

Answer 29

oh yeah, that seems to work :D

Answer 30

And to get the y-intercept, equivalently, set x = 0, and solve for y.

Answer 31

haha -9.75 / .75

Answer 32

*-.75

Answer 33

Okay, fair enough, now, about that y-intercept? :)

Answer 34

y = -3/4x + 9 3/4
y = 9.75

Answer 35

Anyway, y-intercept should be easy if you have it in
y = mx + b form

Answer 36

yeah, that :D

Okay, you've got it, yay XD

Answer 37

:D

Answer 38

I would give you ten medals if I could! :D

Answer 39

Thanks so much!

Answer 40

that won't be necessary... besides, you did most of the work >:)

Answer 41

:)