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View Full Version : Functions mixed with some inequalities


Brittney H
Nov 29, 2006, 10:03 PM
here's a twofer (2in1)

1) How do I go about solving f(x)6x^2-5x and g(x)2x+3, solve f(x)<g(x)


2) A word prob. I can't get... The revenue achieved by selling x graphing calc. is figured to be x(48-0.2x) dollars. The cost of each calc. is $40. How many graphing calc must be sold to make a profit (revenue-cost) of at least $63.80.

Capuchin
Nov 30, 2006, 04:21 AM
For your first question you just plug in the equations, group like terms, make one side 0, factorize and solve.

For the second one, the equation is x(48-0.2x)-40x = 63.8, expand the brackets, group like terms, make it = 0, factorize and solve for your answer.

Instead of factorizing, you can use the equation you should have to solve.