Someone please help me! I have been asking these two questions all day and no ones seems to know how to do them. HELP!
Consider the function f(x) = the quantity x squared minus x minus 12 all over the quantity x plus 3. Describe the graph of this function. Include all discontinuities, intercepts, and the basic shape of the graph.
Ah, it's a simple graphing rational expressions problem.
I will give medal or whatever you want just please can you tell me what the answer is and how you got it?
Begin by factoring the numerator.
Can you do that?
You have x^2 -x -12 in the numerator. Its factors are (x-4)(x+3), but that is all divided by (x+3), so a factor cancels. When this occurs, you know your function has a hole when x = -3.
ok but how do I answer what it is asking?
Plug that x value into the function, that is now f(x) = x-4, where x cannot be -3, to find the y value and the point of the discontinuity.
This is part of the sol'n, lol, the point discontinuity or the "hole" in the function.
oh. so where are my intercepts?
Your remaining function now is f(x) = x-4, which is a line. Your x-intercept can be found by making "y" equal to 0. Similarly, the y-intercept can be found by making the "x" value 0.
This line, remember, has a hole at the point (-3, -7).
So thode would be the intercepts?
and wait would my point of discontinuity be -7?
@KinzaN are you still here?
Yes, sorry. Well since you cancelled the factor (x+3) from both the numerator and the denominator, your hole or point discontinuity occurs when that factor is equal to 0, which is when x = -3. Plugging that value of x=-3 into your new function, y=x-4, results in an answer of -7. So your hole lies at the point f(-3)=-7 or (-3, -7).
wait so my point of discontinuity is -7 then what are my intercepts?
ugh this is confusing
You find values on your x-axis--or x-intercepts--when your y-value is 0. So, 0= x-4 x=4 (4, 0). And, y= 0 - 4 y= -4 (0, -4).
ooooohhhhh ok. and I would describe the shape of the graph as a straight line right?
A line with a slope of one and y-intercept of -4 with a hole at (-3, -7), I guess would be an awesome answer. :)
Lol ok. Can you help me with one more? I am about to post it.
Haha, oookay. :) I'm avoiding my own homework by doing homework for others online, I've got time.
Lol ok THANK YOU!
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