The equation of a circle is (x−11) ²+(y+15) ²=144.
(a) Johnny said that the center of the circle is located at (15, -11). Is Johnny correct? Explain your answer.
(b) Joyce said that the diameter of the circle is 144 units. Is Joyce correct? Explain your answer
Need geometry help?
2019-03-20 12:00 pm
回答 (5)
2019-03-20 12:10 pm
For the equation of circle (x - a)² + (y - b)² = r²
The center is (a, b) and the radius is r.
(a) Incorrect
The equation can be rewritten as: (x - 11)² + [y - (-15)]² = 12²
The center is (11, -15), but NOT (15, -11).
(b) Incorrect
The equation can be rewritten as: (x - 11)² + [y - (-15)]² = 12²
The radius is 12, but NOT 144.
The center is (a, b) and the radius is r.
(a) Incorrect
The equation can be rewritten as: (x - 11)² + [y - (-15)]² = 12²
The center is (11, -15), but NOT (15, -11).
(b) Incorrect
The equation can be rewritten as: (x - 11)² + [y - (-15)]² = 12²
The radius is 12, but NOT 144.
2019-03-22 6:31 pm
(x - 11)² + (y + 15)² = 144……(1)
(x - h)² + (y - k)² = r²……(2)
Compare equation 1 and 2
h = 11, k = -15, r² = 144
r = √144 = 12
radius of circle (r) = 12.
(x - h)² + (y - k)² = r²……(2)
Compare equation 1 and 2
h = 11, k = -15, r² = 144
r = √144 = 12
radius of circle (r) = 12.
2019-03-20 8:46 pm
(x - 11)² + (y + 15)² = 144 = 12²
The typical equation of a circle is: (x - xo)² + (y - yo)² = R² → where:
xo: abscissa of center → 11 in your case
yo: ordinate of center → - 15 in your case
R: radius of circle → 12
The circle is centered at (11 ; - 15)
The typical equation of a circle is: (x - xo)² + (y - yo)² = R² → where:
xo: abscissa of center → 11 in your case
yo: ordinate of center → - 15 in your case
R: radius of circle → 12
The circle is centered at (11 ; - 15)
2019-03-20 12:09 pm
The equation is (x - a)^2 + (y-b)^2 = r^2 where r is the radius, a the offset from the origin for the x coordinate and b the offset for the y coordinate.
so, centre is (a,b) and radius r
Here: centre is (11,-15) and radius 12 (or diameter = 24)
so, centre is (a,b) and radius r
Here: centre is (11,-15) and radius 12 (or diameter = 24)
2019-03-20 12:07 pm
a. C = (11, -15)
b. r^2 = 144
so r = 12 ... d = 24
b. r^2 = 144
so r = 12 ... d = 24
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