Answer:20) MAD = 60°21) <LPN = 57°22) Second and third images, XY is the tangent of circle Z23) x = 11.2Step-by-step explanation:20)<B = <C11x - 3 = 8x + 153x = 18x = 3so<B = <C = 11(3) - 3 = 33 - 3 = 30mAD = 2(30) = 6021)a) <LPN = 1/2(360 - 102 - 144)= 1/2(114)= 57°22)The tangent to a circle is perpendicular to the radius at the point of tangency.a) (7+5)^2 = 7^2 + 10^2(12)^2 = 49 + 100144 ≠ 149First image, XY is not tangent of circle Zb) 20^2 = 12^2 + (8+8)^2400 = 144 + 256400 = 400Second image, XY is the tangent of circle Zc) (11.7 +7.8)^2 = 11.7^2 + 15.6^2380.25 = 136.89 + 243.36380.25 = 380.25Third image, XY is the tangent of circle Z23)x^2 = (8.4+5.6)^2 - (8.4)^2x^2 = 196 - 70.56x^2 = 125.44x = 11.2