Simplify. 14) (7x2 - 8x + 5) - (x3 +6x2 - 11x +18) 15) (2a- 1) (a + 6) (5a + 2) 16) 2m(m - 4) (m2 +1) 17) (204 + 1403 +6a2-90 +2) + (-604 + 303- 15) 18) During the period 1990-2002, the average costs D (in dollars) for a new domestic car and the average costs I (in dollars) for a new imported car can be modeled by: D = 442.14+ + 14.433 and | = -137.6312 + 2705.21 + 15, 117 where t is the number of years since 1990. What operation would you perform to find the difference in average costs (in dollars) for a new imported car and a new domestic car in 20023 19) Since 1970, the number (in thousands) of males, M, and females. F. attending institutes of higher education can be modeled by M = 0.09119 - 4.812 + 1 10t + 5000 and F = 0.191- 1212 + 3501 + 3600 where I is the number of years since 1970. What operation would you need to perform on M and F to find the model for the total number of people attending institutes of higher education? 20) Find a polynomial expression in standard 21) Write the figure's volume as a form for the area of the unshaded region, polynomial in standard form. Show work @ Show work @ 2x + 3 2x - 5