Answer:
(6, 9 ) and r = 3
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
Given
x² + y² - 12x - 18y + 108 = 0
Rearrange the x- terms and the y- terms together and subtract 108 from both sides, that is
x² - 12x + y² - 18y = - 108
To obtain standard form use the method of completing the square
add ( half the coefficient of the x and y terms )² to both sides
x² + 2(- 6)x + 36 + y² + 2(- 9)y + 81 = - 108 + 36 + 81
(x - 6)² + (y - 9)² = 9 ← in standard form
with centre = (6, 9 ) and r = 
= 3
6x/-4 = 6(-1/2)
6x/-4 = - 3...multiply by -4
6x = -3 * -4
6x = 12
x = 2
Answer:
The Answer is D 160
Step-by-step explanation:
Answer:
-4432.5 m . . . or . . . -4.4325 km
Step-by-step explanation:
You can use the formula for average velocity, fill in the given values, and solve for displacement.
average velocity = displacement/time
-98.5 m/s = displacement/(45 s)
Multiply by time:
(-98.5 m/s)(45 s) = displacement = -4432.5 m
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Keeping units with the numbers serves as a check on the math. (m/s)·s = m. The units work the same way variables do: they can be multiplied and divided, raised to a power, canceled. If the units of the problem don't work out right, you're probably doing it wrong. (Note, you can only add and subtract numbers that have the same (identical) units--the same rule as for combining like terms.)
