Exercise 10 Page 125

To evaluate a function for a certain value of x means that we substitute the given value for every instance of x. Let's do this for the given function when x=-2.

n(x)=-1-x+4

Substitute

x= -2

n( -2)=-1-( -2)+4

NegNeg

- (- a)=a

n(-2)=-1+2+4

AddSubTerms

Add and subtract terms

n(-2)=5

When x=-2, the function's value is 5. We will evaluate this function for x=0 and x=5 in the same way using the table below.

x	-1-x+4	n(x)
-2	-1-( -2)+4	5
0	-1- 0+4	3
5	-1- 5+4	-2