Answer:
Step-by-step explanation:
We want to find the equation of a circle with a center at (7, 2) and a point on the circle at (2, 5).
First, recall that the equation of a circle is given by:
Where (<em>h, k</em>) is the center and <em>r</em> is the radius.
Since our center is at (7, 2), <em>h</em> = 7 and <em>k</em> = 2. Substitute:
Next, the since a point on the circle is (2, 5), <em>y</em> = 5 when <em>x</em> = 2. Substitute:
Solve for <em>r: </em>
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Simplify. Thus:
Finally, add:
We don't need to take the square root of both sides, as we will have the square it again anyways.
Therefore, our equation is:
Answer:
Correct.
Step-by-step explanation:
Answer:
The answer is 18x.
Step-by-step explanation:
2x times 9 is 18x because when you multiply 9 times 2, you get 18 and the x carries over.
Answer:
x = 0, π/4, π, 7π/4
Step-by-step explanation:
sin(2x) = √2 sin x
Use double angle formula.
2 sin x cos x = √2 sin x
Move everything to one side.
2 sin x cos x − √2 sin x = 0
Factor.
sin x (2 cos x − √2) = 0
Solve.
sin x = 0, cos x = ½√2
x = 0, π/4, π, 7π/4