Question

use the following function rule to find f(-3.15).
f(x)=7.84 - \frac{x}{1.8}
write your answer as a decimal or whole number.
f(-3.15)=

Explanation:

Step1: Substitute x value

Substitute $x = - 3.15$ into $f(x)=7.84-\frac{x}{1.8}$. So we get $f(-3.15)=7.84-\frac{-3.15}{1.8}$.

Step2: Calculate the fraction part

First, calculate $\frac{-3.15}{1.8}$. $\frac{-3.15}{1.8}=-1.75$. Then $f(-3.15)=7.84-(-1.75)$.

Step3: Simplify the expression

Since subtracting a negative is adding a positive, $7.84-(-1.75)=7.84 + 1.75$.
$7.84+1.75 = 9.59$.

Answer:

$9.59$