21-7=14 is a relate subtraction problem
You have to complete the square on this to get it into standard form of a circle. Move the 8 over to the other side because that's part of the radius. Group together the x terms, take half the linear term which is 8, square it and add it in to both sides. Half of 8 is 4, 4 squared is 16, so add in 16 to both sides. I'll show you in a sec. You don't need to do anything to the y squared term. This just means that the center of the circle does not move up or down, only side to side, right or left. Here's your completing the square before we simplify it down to its perfect square binomial.
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. Now break down the parenthesis into the perfect square binomial and do the addition of the right:
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. This is the standard form of a circle that has a center of (4, 0) and a radius of
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Subtract 4 from both sides.
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Subtract 4 from 36 to get 32.
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Divide both sides by −8. Since −8 is <0, the inequality direction is changed.
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Divide 32 by −8 to get −4.
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<h2>{ Pisces04 }</h2>
The number of girls is 9 :) you add the two ratio numbers to equal 5 you then divide the 15 children by the ratio of 5, which is 3. you then times 2x3 and 3x3 to get the boy and the girls numbers which are 6 &9 so the number of girls is 9