Direct variation is of the form y=kx (inverse variation is of the form y=k/x)
Answer:
B. 3a/a-2
Step-by-step explanation: according to e2020
Answer:
c 15
Step-by-step explanation:
Tangent AB is tangent to circle D at point A. The angle made by a tangent to a circle and a radius of the circle at the point of tangency is a right angle. That means that angle is a right angle, and triangle ABD is a right triangle.
We can use the Pythagoren theorem.
a^2 + b^2 = c^2
x^2 + 20^2 = (x + 10)^2
x^2 + 400 = (x + 10)(x + 10)
x^2 + 400 = x^2 + 10x + 10x + 100
400 = 20x + 100
20x = 300
x = 15
Answer:
142,180 and 10 and 23 and that it
Answer:
Step-by-step explanation:
I used logic and took the easy way around this as opposed to the long, drawn-out algebraic way. I noticed right off that at x = -3 and x = -1 the y values were the same. In the middle of those two x-values is -2, which is the vertex of the parabola with coordinates (-2, 4). That's the h and k in the formula I'm going to use. Then I picked a point from the table to use as my x and y in the formula I'm going to use. I chose (0, 3) because it's easy. The formula for a quadratic is

and I have everything I need to solve for a. Filling in my h, k, x, and y:
and
and
-1 = 4a so

In work/vertex form the equation for the quadratic is

In standard form it's:
