What is the answer to x+36=4x

X + 36 = 4x

First, subtract x from both sides. / Your problem should look like: 36 = 4x - x
Second, simplify 4x - x to get 3x. / Your problem should look like: 36 = 3x
Third, divide both sides by 3. / Your problem should look like:  = x
Fourth, simplify  to get 12. / Your problem should look like: 12 = x
Fifth, switch the problem around (switch sides). / Your problem should look like: x = 12

 x = 12

The density of the cube is 40