Hope im in the right forum post

Basically i have to prove algebraically- the values of k in y=kx+7 that do no intersect the circle x2 +y2=25

What i already know -In my text book i learnt that the radius of the circle is sqrt 25=5

so radius all the way around the circle is 5.

The line y=kx+7 has a y intercept of 7, where it cuts the y axis.

Im not sure about how to go on proving this algebraically, i read an article that you have to sustitute the line equation into the circle one on this site :BBC - Higher Bitesize Maths - The circle : Page 5