What is the center and radius of the circle with the given equation?
1 answer:
Answer:
(- 1, - 4 ) and r = 5
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
To obtain this form from the given equation use the method of completing the square.
Given
x² + y² + 2x + 8y = 8 ( rearrange by collecting x and y terms )
x² + 2x + y² + 8y = 8
To complete the square
add ( half the coefficients of the x/ y terms )² to both sides
x² + 2(1)x + 1 + y² + 2(4)x + 16 = 8 + 1 + 16
(x + 1)² + (y + 4)² = 25 ← in standard form
with centre (h, k ) = (- 1, - 4 ) and r = = 5
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Answer:
The probability that Scott will wash is 2.5
Step-by-step explanation:
Given
Let the events be: P = Purple and G = Green
Required
The probability of Scott washing the dishes
If Scott washes the dishes, then it means he picks two spoons of the same color handle.
So, we have to calculate the probability of picking the same handle. i.e.
This gives:
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So, we have: