Chapter 4, Problem 4QC

To determine

To Evaluate: The value of $3a^2-2ab+c$ where a = 5, b = -3, c = -9

Answer to Problem 4QC

The value of the given polynomial after substituting the values of variables is 96.

Explanation of Solution

Given Information: a = 5, b = -3, c = -9

Calculation:

Substituting the values a = 5, b = -3, c = -9 in the given polynomial $3a^2-2ab+c$.......(1)

  $\begin{array}{l}$ \Rightarrow 3{(5)}^2-2(5)(-3)+(-9)\mathrm{......................}[a=5,b=-3,c=-9in(1)]$\Rightarrow 3(5^2)-2(-15)-\mathrm{9..............................}[Simplify]\\ \Rightarrow 3(25)+30-\mathrm{9.....................................}[Simplify]\\ \Rightarrow 75+30-\mathrm{9..........................................}[Simplify]\\ \Rightarrow 105-\mathrm{9................................................}[Simplify]\\ \Rightarrow 96\end{array}$

Hence, the solution of the given polynomial (1) for a = 5, b = -3, c = -9 is 96.