Question

Find the equation of the circle with centre $(-3,-2)$ and radius $7$

Answer 1

Since the centre of the circle is $(-3,-2)$ and its radius $7$

$\therefore$ The equation of the circle is ${(x-(-3))}^2+{(y-(-2))}^2=7^2$

$\Rightarrow {(x+3)}^2+{(y+2)}^2=49$

$\Rightarrow x^2+6x+9+y^2+4y+4-49=0$

$\Rightarrow x^2+y^2+6x+4y-36=0$