please explain #48 and #49

Thanks! The unit is on inverse functions and relations.

a. Find b. Use the inverse to find the radius of a Use the horizontal line test to determine whether the inverse of each function is also a function. 44. 8(xx) = 14-6x2+1 42. f(x ) = 2x2 43. f (xx) =x3 - 8 47. h ( x ) = x3 + x2 - 6x + 12 45. h(x) = -2x4 - x-2 46. 8 (x ) = 15+x2 - 4x 48. SHOPPING Felipe bought a used car. The sales tax rate was 1.25% of the selling price and he paid $350 in processing and registration fees. Find the selling price if Felipe paid a total of $8395.75. 49. TEMPERATURE A formula for converting degrees Celsius to Fahrenheit is F(x) = 2x + 37 a. Find the inverse F-1(x). Show that F(x) and F 1(x) are inverses. b. Explain what purpose F-1(x) serves. 50. MEASUREMENT There are approximately 1.852 kilometers in a nautical mile. a. Write a function that converts nautical miles to kilometers. b. Find the inverse of the function that converts kilometers back to nautical miles. c. Using composition of functions, verify that these two functions are inverses. 51. MULTIPLE REPRESENTATIONS Consider the functions y = x" for n = 0, 1, 2, .... .AS a. Graphing Use a graphing calculator to graph y = x" for n = 0, 1, 2, 3, and 4. b. Tabular For which values of n is the inverse a function? Record your results in a table. c. Analytical Make a conjecture about the values of n for which the inverse of f(xx) = x" is a function. Assume that n is a whole number. ems Use Higher-Order Thinking Skills 2. MP REASONING If a relation is not a function, then its inverse is sometimes, always, or never a function. Explain your reasoning. 3. OPEN-ENDED Give an example of a function and its inverse. Verify that the two functions are inverses. CHALLENGE Give an example of a function that is its own inverse. MP CONSTRUCT ARGUMENTS Show that the inverse of a linear function y = mx + b, where m # 0 and x # b, is also a linear function