Finding the x is often a student's introduction to algebra. Finding it means solving an equation to find out for which values of x it holds. There are very simple rules to follow to solve an equation correctly. Respecting the order of operations ensures that it is solved correctly. The x must be isolated in one member of the equation. When doing this you must remember to apply the same process to both members.
Steps
Method 1 of 3: Order of Operations
Step 1. Calculate everything in parentheses
- To prove the order of operations we will use this equation: 2 ^ 2 (4 + 3) + 9-5 = x
- 2 ^ 2 (7) + 9-5 = x
Step 2. Calculate all powers
4 (7) + 9-5 = x
Step 3. Starting from left to right, perform all multiplications and divisions
28 + 9-5 = x
Step 4. Still going from left to right, add and subtract
Step 5. 37-5 = x
Step 6. 32 = x
Method 2 of 3: Isolating the x
Step 1. Solve the brackets
- To demonstrate the isolation of x, we will use the example above by replacing a value at the first member with x and equating the equation to the value we calculated.
- 2 ^ 2 (x + 3) + 9-5 = 32
- In this case we cannot resolve the parenthesis because it contains our variable x.
Step 2. Solve the exponents
4 (x + 3) + 9-5 = 32
Step 3. Solve the multiplication
4x + 12 + 9-5 = 32
Step 4. Solve addition and subtraction
- 4x + 21-5 = 32
- 4x + 16 = 32
Step 5. Subtract 16 from each side of the equation
- The x must remain alone. To do this, we subtract 16 from the first member of the equation. Now you have to subtract the second member as well.
- 4x + 16-16 = 32-16
- 4x = 16
Step 6. Divide members by 4
- 4x / 4 = 16/4
- x = 4
Method 3 of 3: Another example
Step 1. 2x ^ 2 + 12 = 44
Step 2. Subtract 12 from each member
- 2x ^ 2 + 12-12 = 44-12
- 2x ^ 2 = 32
Step 3. Divide each member by 2
- (2x ^ 2) / 2 = 32/2
- x ^ 2 = 16
Step 4. Calculate the square root of the members
x = 4
Advice
- Radicals, or roots, are another way of representing powers. The square root of x = x ^ 1/2.
- To verify the result, replace the x in the starting equation with the value you found.