Answer:
x² + y² + 4x - 2y + 1 = 0
Step-by-step explanation:
The equation of a circle is given by the general equation;
(x-a)² + (y-b)² = r² ; where (a,b) is the center of the circle and r is the radius.
In this case; the center is (-2,1)
We can get radius using the formula for magnitude; √((x2-x1)² + (y2-y1)²)
Radius = √((-4- (-2))² + (1-1)²)
= 2
Therefore;
The equation of the circle will be;
(x+2)² + (y-1)² = 2²
(x+2)² + (y-1)² = 4
Expanding the equation;
x² + 4x + 4 + y² -2y + 1 = 4 subtracting 4 from both sides;
x² + 4x + y² - 2y + 4 + 1 -4 = 0
= x² + y² + 4x - 2y + 1 = 0
Answer:
His actual score is 15
Step-by-step explanation:
Here, we are interested in calculating Wayne’s actual score on the ACT
when we say the scores have being standardized, it means the score was reported in terms of the z-score and not the initial raw scores.
Now, mathematically, for the scores to have a negative z-score, it means it is actually below the mean.
The formula for the z-score or standard score is given below;
z-score = (x - mean)/SD
where in this case, x = ? which is the score we are looking for , z-score = -0.5 , mean score = 18 and standard deviation of the scores = 6
So, substituting these values into the z-score equation, we have;
-0.5 = (x-18)/6
x-18 = 6(-0.5)
x -18 = -3
x = -3 + 18
x = 15
24cm
You multiply 6*4=24. Hope this helps! Also can u mark brainliest i need one more :)
Answer:
z is 111 degrees
Step-by-step explanation:
69 ° and z is a linear pair, therefore:
69 + z = 180
z = 180 - 69
z= 111
