Linear equations

Equations in general

Equation means equality for two expressions. An equation is equivalent with the  original equation, if
  • the same number is added for both sides of the equation,
  • the same number is subtracted from both sides of the equation,
  • both sides are multiplied or divided with the same number which is NOT zero.
Standard form:     where x is the variable and a and b are parameters (values unknown but constant). The solution (the root of equation) is    where . If a = 0 and b = 0, then any value of satisfies the equation (identically true). If a = 0 and , the equation has no root (identically false).   Solving linear equations
  1. Remove all brackets and denominators.
  2. Transpose the equation so that terms with variable are in one side of the equation and constants are on the other side.
  3. Combine like terms for to get the equation into a form ax = b.
  4. Divide by the multiplier of the variable.
  5. Check the root by substituting it to the original equation.