x2 + y2 + 6x - 6y + 2 = 0
To complete square to a quadratic equation in its standard form we have:
ax2 + bx + c
Completing squares:
P (x) = (x + b / 2) ^ 2 - b ^ 2/4 + c
Keeping this in mind, we can complete square then:
x2 + y2 + 6x - 6y = -2
(x2 + 6x) + (y2 - 6y) = -2
((x + b / 2) ^ 2 - b ^ 2/4 + c) + ((y + b / 2) ^ 2 - b ^ 2/4 + c) = -2
((x + 6/2) ^ 2 - 6 ^ 2/4 + 0) + ((y + (-6) / 2) ^ 2 - (-6) ^ 2/4 + 0) = -2
((x + 3) ^ 2 - 9) + ((y - 3) ^ 2 - 9) = -2
((x + 3) ^ 2) + ((y - 3) ^ 2) - 9 - 9 = -2
((x + 3) ^ 2) + ((y - 3) ^ 2) - 18 = -2
((x + 3) ^ 2) + ((y - 3) ^ 2) = -2 + 18
((x + 3) ^ 2) + ((y - 3) ^ 2) = 16
((x + 3) ^ 2) + ((y - 3) ^ 2) = 4 ^ 2
Answer:
center: (-3, 3), r = 4
'nine less than three times a number is negative twenty-one.'
No, the absolute value is the distance from zero, positives and negatives don't count in absolute values, it's all about the distance.
Example: |-6| > |4|
Answer:x=
−1
2
y+
5
2
Step-by-step explanation:
Step 1: Add -y to both sides.
2x+y+−y=5+−y
2x=−y+5
Step 2: Divide both sides by 2.
2x
2
=
−y+5
2
x=
−1
2
y+
5
2