Typically, the equation of a circle is given like this: (x-h)^2 + (y-k)^2 = r^2, where r is the radius of the circle and the point (h,k) is the center. To find the value k, you need to put the first equation you have into this form. Standard form requires that you only have the1 y variable, as seen in the parentheses, so you first need to complete the square.
x^2 + y^2 - 2y = 11
x^2 + y^2 - 2y +1 = 11 + 1
x^2 + (y - 1)^2 = 12
And that puts the equation in standard form. k = 1.
Sure but where are the questions?
Answer:
<u>Kevin's height increased 19.05%</u>
Step-by-step explanation:
Height of Kevin at the beginning of sixth grade = 4’10”
Height of Kevin at the end of ninth grade = 5’9”
What was the percentage of increase in Kevin height?
For answering this question, we should convert Kevin's heights to decimal number, this way:
1 feet = 12 inches
4’10” = 4 10/12 = 4.83
5’9” = 5 9/12 = 5.75
Now, let's use the Direct Rule of Three:
Height Percentage
4.83 100
5.75 x
***********************************
4.83x = 5.75 * 100
4.83x = 575
x = 575/4.83
x = 119.05
119.05 - 100 = 19.05
<u>Kevin's height increased 19.05%</u>
