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Find the equation for the circle with center (4,5) and passing through (-3,5).

User Dave Hein
by
5.1k points

1 Answer

1 vote

Answer:


(x-4)^2+(y-5)^2=49

Explanation:

So we want to find the equation of a circle with the center at (4,5) and which passes through the point (-3,5).

First, recall the standard form for a circle, given by the equation:


(x-h)^2+(y-k)^2=r^2

Where (h,k) is the center and r is the radius.

We already know that the center is (4,5). So, substitute 4 for h and 5 for k. Therefore, our equation is now:


(x-4)^2+(y-5)^2=r^2

Now, we need to find the radius.

Remember that our circle passes through the point (-3,5). In other words, when x is -3, y is 5. So, substitute -3 for x and 5 for y to solve for r. Therefore:


(-3-4)^2+(5-5)^2=r^2

Subtract within the parentheses:


(-7)^2+(0)^2=r^2

Square:


49=r^2

Square root:


r=7

Therefore, the radius is 7.

So, substitute 7 into our equation, we will acquire:


(x-4)^2+(y-5)^2=(7)^2

Square:


(x-4)^2+(y-5)^2=49

So, our equation is:


(x-4)^2+(y-5)^2=49

And we're done!

User Michael Pakhantsov
by
6.0k points