Answer:
139968
Step-by-step explanation:
Multiply the all of the numbers together and you have your answer (:
The standard form of the equation of a circle of radius r, with (assuming centre h, k) is given as:
(X-h)^2 + (y-k)^2 = r^2
As we are required to write an equation in standard form for the circle with radius 9 centred at the origin.
Centre(h,k)=(0,0), r=9
Substituting these values into the standard form of the equation of a circle given above:
(X-0)^2 + (y-0)^2 = 9^2
X^2 + y^2 =81
The standard form is x^2 + y^2 =81
I’m pretty sure this is right
Answer:

Step-by-step explanation:

First, we expand the equation using the distributive rule:

Hence, 
Simplify: 
Add like terms:

Subtract 13 from both sides: 
Divide both sides by -8:

Step-by-step explanation:
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