Question

Find the equation of the circle with centre (-9,0) and radius root a
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Answer 1

Answer:

Equation of circle: $x^{2} + y^{2} +18x + 81 - a = 0$

Step-by-step explanation:

Centre coordinates = (-9,0) = (h,k)   .: where h = -9 and k = 0

Radius = $\sqrt{a}$ = r

We know, the general equation of circle is $(x - h)^{2} + (y - k)^{2} = r^{2}$

So, inserting the values in the equation, we get

$(x - (-9))^{2} + (y - 0)^{2} = (\sqrt{a} )^{2}\\(x + 9)^{2} + (y)^{2} = a\\x^{2} +18x +81 + y^{2} = a\\x^{2} + y^{2} +18x + 81 - a = 0$

So, the equation of circle is $x^{2} + y^{2} +18x + 81 - a = 0$

PLEASE MARK IT THE BRAINLIEST

Answer 2

Answer:

sorry I didn't know about this question