Final answer to the problem
Step-by-step Solution
Specify the solving method
Find the break even points of the polynomial $\left(x+1\right)\left(x-4\right)$ by putting it in the form of an equation and then set it equal to zero
Break the equation in $2$ factors and set each equal to zero, to obtain
Solve the equation ($1$)
We need to isolate the dependent variable , we can do that by simultaneously subtracting $1$ from both sides of the equation
Canceling terms on both sides
Solve the equation ($2$)
We need to isolate the dependent variable , we can do that by simultaneously subtracting $-4$ from both sides of the equation
Canceling terms on both sides
Combining all solutions, the $2$ solutions of the equation are
Typically, in break-even points calculation problems, only the positive solutions to the equation are considered