Question 470139
{{{(x-1)^2+(y+3)^2=100}}} Start with the given equation.



{{{(-7-1)^2+(y+3)^2=100}}} Plug in x=-7. The goal now is to solve for y.




{{{(-8)^2+(y+3)^2=100}}} Subtract




{{{64+(y+3)^2=100}}} Square -8 to get 64



{{{(y+3)^2=100-64}}} Subtract 64 from both sides.



{{{(y+3)^2=36}}} Subtract



{{{y+3=""+-sqrt(36)}}} Take the square root of both sides.



{{{y+3=sqrt(36)}}} or {{{y+3=-sqrt(36)}}} Break up the "plus/minus"



{{{y+3=6}}} or {{{y+3=-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)