SOLUTION: if f(x)=2x^2-7x+3,find the answer to 1. f(2) 2. f(-3)

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: if f(x)=2x^2-7x+3,find the answer to 1. f(2) 2. f(-3)      Log On


   

Question 111568: if f(x)=2x^2-7x+3,find the answer to
1. f(2)
2. f(-3)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

f%28x%29=2x%5E2-7x%2B3 Start with the given function.


f%282%29=2%282%29%5E2-7%282%29%2B3 Plug in x=2. In other words, replace each x with 2.


f%282%29=2%284%29-7%282%29%2B3 Evaluate %282%29%5E2 to get 4.


f%282%29=%2B8-7%282%29%2B3 Multiply 2 and 4 to get 8


f%282%29=%2B8-14%2B3 Multiply -7 and 2 to get -14


f%282%29=-3 Now combine like terms


-----------Now let's evaluate another value---------


f%28x%29=2x%5E2-7x%2B3 Start with the given function.


f%28-3%29=2%28-3%29%5E2-7%28-3%29%2B3 Plug in x=-3. In other words, replace each x with -3.


f%28-3%29=2%289%29-7%28-3%29%2B3 Evaluate %28-3%29%5E2 to get 9.


f%28-3%29=%2B18-7%28-3%29%2B3 Multiply 2 and 9 to get 18


f%28-3%29=%2B18%2B21%2B3 Multiply -7 and -3 to get 21


f%28-3%29=42 Now combine like terms