Answer:
x = 5
Step-by-step explanation:
Take your starting equation:
5x - 6 = 2x + 9
Your first step should be to isolate the variable, X, by having it on only one side of the equation. This can be done by subtracting one of the X values (either 5x or 2x) from either side, but I recommend the side with 2x since it's a smaller value and won't result in a negative.
(This is the right side of the equation)
2x + 9
- 2x
= 9
We need to do the same thing on the other side of the equation too, to balance both sides:
(This is the left side of the equation)
5x - 6
- 2x
= 3x - 6
This is our equation now:
3x - 6 = 9
The next step is to isolate X further by removing any constants (regular numbers) from the side with X. Since the constant on that side is -6, we need to add 6 to that side so that it's cancelled out, and do the same on the other side to balance.
(This is the left side of the equation)
3x - 6
+ 6
= 3x
And now for the other side:
(This is the right side of the equation)
9
+ 6
= 15
This is our current equation:
3x = 15
The final step is to get X completely isolated. X is being multiplied by 3, so we need to divide both sides of the equation by 3 to finally get the value of X.
(This is the left side of the equation)
3x
÷ 3
= x
And now for the other side:
(This is the right side of the equation)
15
÷ 3
= 5
Our final equation:
x = 5
We can check our answer by taking the final X value, 5, and inserting it into our beginning equation.
This is the beginning equation, as a reminder:
5x - 6 = 2x + 9
Replace all instances of X with its value, 5:
(5 · 5) - 6 = (2 · 5) + 9
After simplifying, the result is:
19 = 19, which means the X value is correct.
