Find Equation of line to solve a cubic function

Question

A cubic graph for $x^3 + 4x^2 + 2x - 4$ is given.

Question is: Find an equation of the line you would draw on that graph to solve graphically: $x^3 + 4x^2 + 3x - 1 = 0.$

Give the answer in $y = mx + c$ form.

Answer 1

$x^3 + 4x^2 + 3x - 1 = 0$ $\Leftrightarrow$ $x^3 + 4x^2 + 2x - 4 =-x-3 $

Then answer is $y=-x-3$.

Solutions of $x^3 + 4x^2 + 3x - 1 = 0$ is intersection points $$x\approx0.247,\quad x\approx-1.445,\quad x\approx-2.802$$