5. PA is tangent to circle O at A, secant PBC is drawn, PB = 4, and BC = 12. 6. Secants PQR and PST are drawn to a Find PA. circle from point P. If PR = 24, PQ = 6, and PS = 8, determine and state the length of PT. B C R S T 7. CBA and CED are secants. AC = 12, 8. PS is a tangent to circle O at point S and BC = 3, and DC = 9. Find EC. PQR is a secant. If PS = x, PQ = 3, and PR = x + 18, find x. B C A E R O D S (Not drawn to scale)