We want to recast the equation into the standard form equation for a circle centered at (h, k) with radius r. That equation is
... (x -h)² + (y -k)² = r²
Start by completing the square for both x-terms and y-terms.
... x² - 4x + y² + 4y = k
To do that, add the squares of half the coefficients of the x- and y-terms.
... x² - 4x + (-2)² + y² + 4y + 2² = k + (-2)² + 2²
... (x -2)² + (y +2)² = k + 8 = r² . . . . . this is now equal to the square of the radius, so we have
... k + 8 = 6² = 36
Subtracting 8 gives
... k = 28 . . . . . . . matches selection D)
All you have to do is find the square root of 2601. You can use the square root key on your calculator or you can do 2601∧1/2
The answer is 51.
Answer:
20
Step-by-step explanation:
To solve this you have to make a system of equations.
Since the father and son's age sum up to 60, the first equation will be:
f + s = 60
Secondly, since the father's age is 5 times the age of the son 6 years ago the equation will be:
6 - (5s) = f
Now, you have to solve the first equation to let it equal to s
f + s = 60
f = 60 - s
Plug in
6 - 5s = 60 - s
+s +s
6 - 4s = 60
-6 -6
---------------------
-4s = 54
----- -----
-4 -4
s ≅ 14
14 + 6 = 20
The solution is (-2,4) she right both have the same solution because if you solve both of them you will get (-2,4)