SOLUTION: {{{f(x)=system( matrix(2,3,-2x-2,"if",x<4,-4x+5,"if",x>=4) )}}} Determine {{{f(3)}}} a. -3 b. -6 c. -8 d. -14

Algebra ->  Algebra  -> Functions -> SOLUTION: {{{f(x)=system( matrix(2,3,-2x-2,"if",x<4,-4x+5,"if",x>=4) )}}} Determine {{{f(3)}}} a. -3 b. -6 c. -8 d. -14      Log On

Ad: Algebrator™ solves your algebra problems and provides step-by-step explanations!
Ad: Algebra Solved!™: algebra software solves algebra homework problems with step-by-step help!

   

Question 160176: f%28x%29=system%28+matrix%282%2C3%2C-2x-2%2C%27if%27%2Cx%3C4%2C-4x%2B5%2C%27if%27%2Cx%3E=4%29+%29
Determine f%283%29
a. -3
b. -6
c. -8
d. -14
Answer by Edwin McCravy(6935) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29=system%28+matrix%282%2C3%2C-2x-2%2C%27if%27%2Cx%3C4%2C-4x%2B5%2C%27if%27%2Cx%3E=4%29+%29
Determine f%283%29
a. -3
b. -6
c. -8
d. -14
 
Look inside the parentheses of "f%283%29"

What is in there?  Answer: 3

Look inside the parentheses of "f%28x%29"

What is in there?  Answer: x

What does that mean?  Answer: That x is this problem is 3.

Is 3 less than 4 or is 3 greater than or equal 4?  
Answer: 3 is less than 4

Since x, which is 3, is less than 4, then what does this f%28x%29=system%28+matrix%282%2C3%2C-2x-2%2C%27if%27%2Cx%3C4%2C-4x%2B5%2C%27if%27%2Cx%3E=4%29+%29 
tell you to use, -2x-2 or -4x%2B5? Answer: -2x-2

How do you substitute 3 for x into -2x-2?  
Answer: -2x-2=-2%283%29-2=-6-2=-8

Then what is the final answer?  Answer: -8.

Edwin