3. Is XY Tangent to circle Z?
Y
12 X
(20
Z
18

XY is a tangent

Step-by-step explanation:

Given

Required

Is XY a tangent?

XY is a tangent if:

Because XY should make a right angle at point X with the circle

Where

So, we have:

This gives:

Yes, XY is a tangent

i think its a and d

step-by-step explanation:

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.