Quadratic formula using roots to solve for x gives you two values of x
Answer:
The answer is c
Step-by-step explanation:
Yeahhhhh
Answer:
The equation of the quadratic in standard form is:
![y=-2x^2-8x-2](https://tex.z-dn.net/?f=y%3D-2x%5E2-8x-2)
Step-by-step explanation:
Since they give us the information about where the vertex of the parabola is located, and one extra points where it passes through, we can use the general form of a quadratic in vertex form:
![y-y_v=a\,(x-x_v)^2](https://tex.z-dn.net/?f=y-y_v%3Da%5C%2C%28x-x_v%29%5E2)
where
is the location of the vertex (in our case the point (-2,6).
Therefore the equation above becomes:
![y-y_v=a\,(x-x_v)^2\\y-6=a\,(x-(-2))^2\\y-6=a\,(x+2)^2](https://tex.z-dn.net/?f=y-y_v%3Da%5C%2C%28x-x_v%29%5E2%5C%5Cy-6%3Da%5C%2C%28x-%28-2%29%29%5E2%5C%5Cy-6%3Da%5C%2C%28x%2B2%29%5E2)
Now,we can use the fact that the point (-4,-2) is also a point of the graph, to find the value of the parameter
:
![y-6=a\,(x+2)^2\\-2-6=a\,(-4+2)^2\\-8=a\,(-2)^2\\-8=a\,*4\\a=-2](https://tex.z-dn.net/?f=y-6%3Da%5C%2C%28x%2B2%29%5E2%5C%5C-2-6%3Da%5C%2C%28-4%2B2%29%5E2%5C%5C-8%3Da%5C%2C%28-2%29%5E2%5C%5C-8%3Da%5C%2C%2A4%5C%5Ca%3D-2)
Then, the equation of the quadratic with such characteristics becomes:
![y-6=-2\,(x+2)^2\\y-6=-2x^2-8x-8\\y=-2x^2-8x-2](https://tex.z-dn.net/?f=y-6%3D-2%5C%2C%28x%2B2%29%5E2%5C%5Cy-6%3D-2x%5E2-8x-8%5C%5Cy%3D-2x%5E2-8x-2)
which is the equation of the quadratic in standard form.
Answer:
About 145 miles.
Explanation:
Assume that the distance from the center of the earth to any point on the earth's surface is 4,000 miles.
Step-by-step explanation:
r
=
4000
v
=
13796
5280
(divide by 5280 to convert to miles)
Using Pythagorean's Theorem:
a
2
+
b
2
=
c
2
a
2
+
4000
2
=
(
4000
+
13796
5280
)
2
a
2
=
(
4000
+
13796
5280
)
2
−
4000
2
a
=
√
(
4000
+
13796
5280
)
2
−
4000
2
≈
144.6
Answer:
I would say c because if you have -2-(-4) you really have -2 + 4 so it would be a positive 2 instead of -2