We are given the following expression:
[tex]8x-5y[/tex]We are asked to evaluate the expression at;
[tex]\begin{gathered} x=4 \\ y=-9 \end{gathered}[/tex]To determine the numerical value of the expression at the given points we will substitute the values, like this:
[tex]8(4)-5(-9)[/tex]Now, we solve the products:
[tex]8(4)-5(-9)=32+45[/tex]Now, we solve the addition:
[tex]32+45=77[/tex]Therefore, the value of the expression is 77.
