f(-5) for f(x) = {7x if x ≤ -1

{x-9 if x > -1

f(-5) for f(x) = {7x if x ≤ -1

{x-9 if x > -1

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Stamford, CT

Hi Jay,

we have to find the value for f(-5)

The equation f(x)=7x gives the value of f(x) when x is less than or equal to -1.

The equation f(x)=x-9 gives the value of f(x) when x is greater than -1.

since -5 is less than -1

so we will take the equation f(x)=7x to find the value for f(-5)

f(-5)=7(-5)=-35

Castle Rock, WA

In this example we will be substituting the value (-5) for x in the expression given.

The critical question is:

is -5 more or less than -1?

If it is less, then you use the first expression: f(x) = 7x.

If it is more, then you use the second expression: f(x) = x-9.

The actual numerical evaluation will proceed exactly as you would expect after that point.

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