If the axis of symmetry is x=-1, the vertex will have x-coordinate -1.
The point (0, 5) cannot be the vertex. The friend is not correct.
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If the point (1, 5) is on the graph so is the image of that point when it is reflected across the axis of symmetry. That image point is (-3, 5). A parabola that goes through points (1, 5) and (-3, 5) will not go through point (0, 5).
Answer:
Step-by-step explanation:

First, on the right-hand side of the equation, let's distribute the
to each term in the parenthesis:

Now, let's move all the terms with an
to the left-hand side, and everything else to the right-hand side of the equation:

Let's combine like terms:

Finally, let's divide each side by
to get
by itself on the left-hand side of the equation:

13 9/10
This is just a math equation. Just add 12 1/2 to 1 2/5 and remember that the bottoms of fractions have to be the same and if you change the bottoms, you have to change the top just as much :)
Answer:
x = 3.5
Step-by-step explanation:
Triangle to the right:
4^2 + x^2 = 8^2
16 + x^2 = 64
y^2 = 48
Triangle to the left:
x^2 + 6^2 = 48
x^2 + 36 = 48
x^2 = 12
x = sqrt(12)
x = 3.5
The equation of a circle is (x - h)^2 + (y - k)^2 = r^2
x and y are left alone in a circle equation, while h and k are the coordinates of the center.
Thus, our equation is (x - 7)^2 + (y + 2)^2 = 61