SOLUTION: This question seems to make no sense to me , at a point i thought i had something but i just cant solve pleasee help me: Two points on the circle given by the equation (x-1)^2+(

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Question 470139: This question seems to make no sense to me , at a point i thought i had something but i just cant solve pleasee help me:
Two points on the circle given by the equation (x-1)^2+(y+3)^2=100 have x-coordinate -7.what is the y coordinates of those two points?
now that i reread this problem im thinking the numbers in the actual equation are irrelevant but im not sure. your help is appreciated thsnk you.
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
%28x-1%29%5E2%2B%28y%2B3%29%5E2=100 Start with the given equation.


%28-7-1%29%5E2%2B%28y%2B3%29%5E2=100 Plug in x=-7. The goal now is to solve for y.



%28-8%29%5E2%2B%28y%2B3%29%5E2=100 Subtract



64%2B%28y%2B3%29%5E2=100 Square -8 to get 64


%28y%2B3%29%5E2=100-64 Subtract 64 from both sides.


%28y%2B3%29%5E2=36 Subtract


y%2B3=%22%22%2B-sqrt%2836%29 Take the square root of both sides.


y%2B3=sqrt%2836%29 or y%2B3=-sqrt%2836%29 Break up the "plus/minus"


y%2B3=6 or y%2B3=-6 Take the square root of 36 to get 6.


y=6-3 or y=-6-3 Subtract 3 from both sides.


y=3 or y=-9 Subtract


So the y-coordinates are y=3 and y=-9


So the two points are (-7,3) and (-7,-9)