A circle has its center at (1,4) and a radius of 2 units what is the equation of the circle

Answer: x² + y² - 2x - 8y + 13 = 0

Step-by-step explanation:

the equation of the circle is in the form (x - a) ² + (y - b) ² = r²

where (a, b) is the center of the circle and r is the radius

hence the equation is

(x - 1) ² + (y - 4) ² = 2²

x²-2x+1+y²-8y+16 = 4

x² + y² - 2x - 8y + 17 = 4

x² + y² - 2x - 8y = - 13

x² + y² - 2x - 8y + 13 = 0

The unsimplified answer to the smart person above (the answer to the test) is

(x-1) ^2 + (y-4) ^2=4