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

19.side- angle- side

20. angle- side- angle

step-by-step explanation:

let m = monomial

let t = trinomial

so, m times t = t.

monomial times a trinomial = another trinomial.