How to use this linear equation calculator
What a and b mean
In ax + b = 0, a is the number multiplying x and b is the constant number. The unknown is x. Enter only the two real coefficients, not the letter x or a full equation.
How the answer is found
The calculator moves b to the other side and divides by a: ax = −b, so x = −b/a. The displayed answer uses at most two ordinary decimal places, while very small nonzero answers use scientific notation.
What happens when a is zero
If a = 0 and b = 0, the statement is 0 = 0, so every real number works. If a = 0 and b is not zero, the statement cannot be true and there is no solution.
Examples
2x − 8 = 0
Enter a = 2 and b = −8. The answer is x = 4.
−3x + 6 = 0
Enter a = −3 and b = 6. The answer is x = 2.
0x + 5 = 0
Enter a = 0 and b = 5. There is no solution.
Frequently asked questions
Do I type the x?
No. Type only the number in front of x into a and the constant number into b.
How do I enter subtraction?
Put the minus sign in the coefficient. For x − 5 = 0, enter a = 1 and b = −5.
Can I paste a full equation?
No. This focused calculator accepts coefficients only. Rearrange the equation so the right side is zero first.
Are decimals allowed?
Yes. Use a decimal point, such as 2.5, in every language version.