pls just do 7-17 odds

bx + ay = 1 7. a. Draw the graphs of 9x - 6y = 3 and 6x - 4y = 10. Then solve the system of equations by using determinants. b. If ax + by = c and dx + ey = f have parallel line graphs, what determi nant must be equal to zero? 8. a. Draw the graphs of 12x + 8y = -4 and 6x + 4y = -2. Then solve the system of equations by using determinants. b. If ax + by = c and dx + ey = f have the same graph, what determinants must be equal to zero? In Exercises 9-14, find the area of each figure, given points P(4, 3), Q(7, -1), R(2, 3), S(-3, 6), T(-5, 4), and V(-2, -5). 9. APOR 10. APQS 11. ARST 12. A PSV 13. O with sides PR, PS 14. O with sides PS, PT 15. Discussion If the "area" of A LMN is zero, what can you conclude about points L, M, and N? 16. Discussion If a parallelepiped with sides DE, DF, and DG has "zero vol- ume," what can you say about points D, E, F, and G? In Exercises 17-19, solve each system of equations by using Cramer's rule. B 17. x - 2y + 3z = 2 18. 4x - 2y + 3z = 2 2x - 3y + z = 1 19. 3x - 2y + 2=1 5x - 6y + 2z = -1 3x - y + 2z = 9 2x + y - 32 =1 3x + 4y - 5z = 7 x + 2y + 2z =4