Solve the question 2x-3+4x=21

x = 4

First collect the like terms:

2x - 3 + 4x = 21

6x - 3 = 21

Next, move constant to the right side and change it's sign:

6x = 21 + 3

Next, add the numbers:

6x = 23

Finally, divide both sides by 6:

6x / 6 = 24 / 6

(Any expression divided by itself equals 1)

x = 24 / 6 ...

x = 4

6x - 3 = 21 21 - 3 = 18 divided by 6 is 3 your answer is 3