I’m guessing it’s 9x^2 -6x + 1 but this is basically just one. (1/3,0) use desmos if you’re curious
Part 1We are given
![x^2-21x=-4x](https://tex.z-dn.net/?f=x%5E2-21x%3D-4x)
. This can be rewritten as
![x^2-18x=0](https://tex.z-dn.net/?f=x%5E2-18x%3D0)
.
Therefore, a=1, b=-18, c=0.
Using the quadratic formula
![x=\frac{18\pm 18}{2}](https://tex.z-dn.net/?f=x%3D%5Cfrac%7B18%5Cpm%2018%7D%7B2%7D)
The values of x are
Part 2Since the values of y change drastically for every equal interval of x, the function cannot be linear. Therefore, the kind of function that best suits the given pairs is a
quadratic function. Part 3.The first equation is
![y=x^2+2](https://tex.z-dn.net/?f=y%3Dx%5E2%2B2)
.
The second equation is
![y=3x+20](https://tex.z-dn.net/?f=y%3D3x%2B20)
.
We have
![x^2-3x-18=0](https://tex.z-dn.net/?f=x%5E2-3x-18%3D0)
Factoring, we have
![\left(x-6\right)\left(x+3\right)=0](https://tex.z-dn.net/?f=%5Cleft%28x-6%5Cright%29%5Cleft%28x%2B3%5Cright%29%3D0)
Equating both factors to zero.
![x_2+3=0\rightarrow x_2=-3](https://tex.z-dn.net/?f=x_2%2B3%3D0%5Crightarrow%20x_2%3D-3)
When the value of x is 6, the value of y is
![y=3\left(6\right)+20=38](https://tex.z-dn.net/?f=y%3D3%5Cleft%286%5Cright%29%2B20%3D38)
When the value of x is -3, the value of y is
![y=3\left(-3\right)+20=11](https://tex.z-dn.net/?f=y%3D3%5Cleft%28-3%5Cright%29%2B20%3D11)
Therefore, the solutions are (6,38) or (-3,11)
Answer:
c) the line should not be solid. the line should be dashed