Answer:
10
Step-by-step explanation:
The radius is the magnitude of the complex number that is the difference between any point on the circle and the center point. A suitable calculator can tell you that magnitude:
║(8+7i) - (2-i)║ = √((8-2)² +(7-(-1))²) = √(36+64) = √100 = 10
Answer:
y = x - 3
Step-by-step explanation:
The equation of a line in slope- intercept form is
y = mx + c ( m is the slope and c the y- intercept )
Here m = , thus
y = x + c ← is the partial equation
To find c substitute (3, - 1) into the partial equation
- 1 = 2 + c ⇒ c = - 1 - 2 = - 3
y = x - 3 ← equation of line