The given function `h(x)= 11/(x-9)+9` is the same as:
`h(x)= 11/(x-9)+9 *(x-9)/(x-9)`
`h(x)= 11/(x-9)+(9x-81)/(x-9)`
`h(x)=(11+(9x-81))/(x-9) `
`h(x)=(11+9x-81)/(x-9) `
`h(x) = (9x-70)/(x-9)`
To be able to graph the rational function `h(x) =(9x-70)/(x-9)` or `y =(9x-70)/(x-9)` , we solve for possible asymptotes. Note: `h(x)=y` .
Vertical asymptote exists at `x=a ` that will satisfy `D(x)=0` on a rational function `f(x)= (N(x))/(D(x))` . To solve for the vertical asymptote, we equate the expression at denominator side to `0` and solve for `x` .
In `h(x) =(9x-70)/(x-9)` , the `D(x)=x-9.`
Then,` D(x) =0 ` will be:
`x-9=0`
`x-9+9=0+9`
`x=9`
The vertical asymptote exists at `x=9` .
To determine the horizontal asymptote for a given function: `f(x) = (ax^n+...)/(bx^m+...)` , we follow the conditions:
when `n lt m ` horizontal asymptote:` y=0`
`n=m ` horizontal asymptote: ` y =a/b`
`ngtm ` horizontal asymptote: NONE
In `h(x) = (9x-70)/(x-9)` , the leading terms are `ax^n=9x or 9x^1` and `bx^m=x or 1x^1` . The values `n =1` and `m=1` satisfy the condition: n=m. Then, horizontal asymptote exists at ` y=9/1 or y =9`.
To solve for possible y-intercept, we plug-in `x=0` and solve for `y`.
`y =(9*0-70)/(0-9)`
`y =(-70)/(-9) `
`y = 70/9 or 7.778 ` (approximated value)
Then, y-intercept is located at a point `(0, 7.778).`
To solve for possible x-intercept, we plug-in `y=0` and solve for `x.`
`0 =(9x-70)/(x-9)`
`0*(x-9)= (9x-70)/(x-9)*(x-0)`
`0 =9x-70`
`0+70=-9x-70+70`
`70=9x`
`70/9=(9x)/9`
`x=70/9 or 7.778`
Then, x-intercept is located at a point `(7.778,0).`
Solve for additional points as needed to sketch the graph.
When `x=8,` the `y = (9*8-70)/(8-9)=2/(-1)=-2` . point: `(8,-2)`
When `x=10` , the `y = (9*10-70)/(10-9)=20/1=20` . point: `(10,20)`
When `x=20` , the `y =(9*20-70)/(20-9)=110/11=10` . point: `(20,10)`
When `x=-2` , the` y =(9*(-2)-70)/(-2-9)= (-88)/(-11)=8` . point: `(-2,8)`
Applying the listed properties of the function, we plot the graph as:
You may check the attached file to verify the plot of asymptotes and points.
As shown on the graph, the domain: `(-oo, 9)uu(9,oo)`
and range: `(-oo,9)uu(9,oo).`
The domain of the function is based on the possible values of `x.` The `x=9` is excluded due to the vertical asymptote.
The range of the function is based on the possible values of `y` . The `y=9` is excluded due to the horizontal asymptote.
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