How do you calculate variables ex .) ab+cd=e

When turned about its axis of rotation, which shape could have created this three-dimensional object?

Follow these steps using the algebra tiles to solve the equation −5x + (−2) = −2x + 4. 1. add 5 positive x-tiles to both sides and create zero pairs. 2. add 4 negative unit tiles to both sides and create zero pairs. 3. divide the unit tiles evenly among the x-tiles. x =

Can someone check if i did this correct. it’s number 4 if you’re wondering.