Q43. - Algebra 1

Question

Examples 4 and 5 If $f\left(x\right)=-2x-3$ and $g\left(x\right)=x^2+5x,$ find each value. (P. 50)

$5\left[f\right(d\left)\right]$

Step-by-Step Solution

Answer

The value of the function is $-10d-15$

Step 1. Interpreting of function.

$f\left(d\right)$ Indicates the value of function $f\left(x\right)$ at $x=d$

Step 2. Apply substitution method.

Substitute $x=d$ into the function $f\left(x\right)$

$\begin{array}{l}f\left(d\right)=-2\left(d\right)-3\\ f\left(d\right)=-2d-3\end{array}$

Step 3. Further calculation.

$\begin{array}{l}5\left[f\left(d\right)\right]=5\left[-2d-3\right]\\ 5\left[f\left(d\right)\right]=-10d-15\end{array}$

Thus, the value of the function is $-10d-15$