17 + x = 68
We can subtract 17 from both sides of the equation to find the value of x.
68 - 17 = x
Answer: x = 51, so Jeanne needs $51 to buy the game.
In the problem above, x is a variable. The symbols 17 + x = 68 form an algebraic equation. Let's look at some examples of writing algebraic equations.
Example 1: Write each sentence as an algebraic equation.
Sentence Algebraic Equation
A number increased by nine is fifteen. y + 9 = 15
Twice a number is eighteen. 2n = 18
Four less than a number is twenty. x - 4 = 20
A number divided by six is eight.
Example 2: Write each sentence as an algebraic equation.
Sentence Algebraic Equation
Twice a number, decreased by twenty-nine, is seven. 2t - 29 = 7
Thirty-two is twice a number increased by eight. 32 = 2a + 8
The quotient of fifty and five more than a number is ten.
Twelve is sixteen less than four times a number.