The vertex of the parabola is (-3, 9)
In order to find the vertex of any quadratic, you start by finding the x-value of said vertex. This can be done using the equation below.
-b/2a
In this equation 'a' refers to the coefficient of x^2 (-1) and 'b' refers to the coefficient of x (-6). So then we can plug into that equation using those values.
-b/2a
-(-6)/2(-1)
6/-2
-3
Now that we have the x value, we can substitute that value into the equation to find the y value.
f(x) = -x^2 - 6x
f(x) = -(-3)^2 - 6(-3)
f(x) = -(9) + 18
f(x) = 9
Therefore our point is (-3, 9)
Im taking the test right now I’ll give you the answer
Answer:
109 inch
Step-by-step explanation:
we know that
![tan\theta=\frac{Perp}{Base} \\\theta=70\\Base=40 in](https://tex.z-dn.net/?f=tan%5Ctheta%3D%5Cfrac%7BPerp%7D%7BBase%7D%20%5C%5C%5Ctheta%3D70%5C%5CBase%3D40%20in)
So,
![tan(70)=\frac{Perp}{40} \\\\2.747=\frac{Perp}{40} \\\\2.747\times40=Perp\\\\Perp=109\quad in](https://tex.z-dn.net/?f=tan%2870%29%3D%5Cfrac%7BPerp%7D%7B40%7D%20%5C%5C%5C%5C2.747%3D%5Cfrac%7BPerp%7D%7B40%7D%20%5C%5C%5C%5C2.747%5Ctimes40%3DPerp%5C%5C%5C%5CPerp%3D109%5Cquad%20in)
So, length of lamppost is 109 inch
the answer to many questions like this are on math Step-by-step explanation: