Answer:
a : c = 7 : 10
Step-by-step explanation:
The two ratios (a : b and b : c) both have b in common, so to work out what a : c is, we can use b to 'bridge' the two ratios together.
However, in a : b, b is 4. But in b : c, b is 2. We need to make sure b is the same in both ratios before we can combine the ratios together. The easiest way to do this is to multiply b : c by 2 to get b : c = 4 : 10. Now b is 4 in both ratios.
So now, we can combine the two ratios together to get a : b : c = 7 : 4 : 10. Since we only want a : c though, we can just drop the b and get a : c = 7 : 10. No simplifying is necessary since the ratio is already in its simplest form.
Hope that helps! :)
Answer:
(a) (x-2)^2 +(y-2)^2 = 16
(b) r = 2
Step-by-step explanation:
(a) When the circle is offset from the origin, the equation for the radius gets messy. In general, it will be the root of a quadratic equation in sine and cosine, not easily simplified. The Cartesian equation is easier to write.
Circle centered at (h, k) with radius r:
(x -h)^2 +(y -k)^2 = r^2
The given circle is ...
(x -2)^2 +(y -2)^2 = 16
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(b) When the circle is centered at the origin, the radius is a constant. The desired circle is most easily written in polar coordinates:
r = 2
Answer:
x < 7
Step-by-step explanation:
7x < 49 (Given)
x < 7 (Divided 7 on both sides)
