Chapter 7, Problem 17GR

To determine

Toevaluate:The given expression $b-{\left(3a\right)}^2$ for given value of a andb .

Answer to Problem 17GR

The value of expression $b-{\left(3a\right)}^2$ for $a=-2$ and $b=5$ is -31.

Explanation of Solution

Given information:

The expression $b-{\left(3a\right)}^2$ to be evaluated for $a=-2$ and $b=5$

Methodused:

The expression is calculated by substituting values of $a=-2$ and $b=5$ .

The given expression is $E\left(a,b\right)=b-{\left(3a\right)}^2$ .

  $\Rightarrow E\left(-3,5\right)=5-{\left(3(-2)\right)}^2$

  $\Rightarrow E\left(-3,5\right)=5-{\left(-6\right)}^2$

  $\Rightarrow E\left(-3,5\right)=5-36$

  $\Rightarrow E\left(-3,5\right)=-31$

Thus, the value of expression $b-{\left(3a\right)}^2$ for $a=-2$ and $b=5$ is -31.

Conclusion:

The value of expression $b-{\left(3a\right)}^2$ for $a=-2$ and $b=5$ is -31.