Question

-r(a + b) if r = -2, a = 4, and b = -5

Answer 1

`\begin{gathered} -r(a+b) \\ \\ r=-2 \\ a=4 \\ b=-5 \end{gathered}`

To evaluate the given equation using the given values for each variable:

-Substitute the corresponding values in the equation:

`-(-2)(4+(-5))`

- Eliminate parentheses:

Use the next sing rules:

`\begin{gathered} +(+)=+ \\ +(-)=- \\ -(+)=- \\ -(-)=+ \end{gathered}`
`\begin{gathered} =2(4-5) \\ \end{gathered}`

- Solve operations in parentheses:

`=2(-1)`

- Solve multiplication:

`=-2`Then, the solution is -2