When an equation of circle is expressed in the form:
(x-h)^2 + (y-k)^2 = r^2
(h, k) is the center and r is the radius.
The center = the coordinate you have plotted on the graph.
Radius = how many units long the circle extends to.
SO, let's plug this in.
Coordinate plotted = (0, -4)
0 = h
-4 = k
(x - {0})^2 + (y - {-4})^2 = 2^2
(x - 0)^2 + (y + 4)^2 = 4
(whenever we have two negative signs next to each other, it turns the digit to the right of the final negative sign positive.)
Now we are left with this final equation as a solution:
x^2 + (y + 4)^2 = 4.
I hope this helped~!
The standard form of a circle:
- the coordinates of a center of a circle
- the radius
We have:
the center:
the radius:
substitute
wavelength of the waves.
speed of the waves.
mood of the waves.
Part B: Solve this equation justifying each step with an algebraic property of equality. (6 points)
Part C: How many movie tickets did Erica purchase last month?
A) Let t represent the number of tickets Erica bought. The the equation describing her rebates can be written as
... 3t + 0.80×15 = 18
B) Here's the solution to the equation.
... 3t + 12 = 18 . . . . . . simplify; rules of arithmetic
... 3t = 6 . . . . . . . . . . .subtract 12; subtraction property of equality
... t = 2 . . . . . . . . . . . . divde by 3; division property of equality
C) Erica bougth 2 movie tickets last month.
(2x-1)^4 = 64