Question 1085683
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Find the equation, in standard form, of the circle being described in each item.


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1. center (2/5, - 3/7), radius 11        {{{(x-2/5)^2 + (y+3/7)^2}}} = {{{11^2}}}


2. diameter with endpoints (-1,3) and (9,1)   {{{(x-4)^2+(y-2)^2}}} = {{{(10^2+2^2)/4}}}


3.diameter with endpoints (3,-5) and (6,4)


4.center (-6,-3), through (-10,3)


5. center (5,7), tangent to the x-axis    {{{(x-5)^2+(y-7)^2}}} = {{{7^2}}}


6. center (-4,9), tangent to the x-axis   {{{(x+4)^2+(y-9)^2}}} = {{{9^2}}}



And last problem, i need help from this.

Find the equations of the lines described. Give your answers in the form y=mx+b.

here i use (x²+y²-18x-2y+48=0 at x=4) using same on 3 problems

1.tangent lines to x²+y²-18x-2y+48=0 at points where x=4

2. tangent lines to x²+y²-22x+12y+137=0 at points where x=15
3. tangent lines to x²+y²-16x-12y+87=0 at points where y=4
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When you submit many problems in one post, you work against yourself.