7 VOCABULARY An equation is a mathematical statement

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VOCABULARY An equation is a mathematical statement that two expressions are equal. You can think of a correct equation as a balanced scale. 3+2 5

VOCABULARY Equations may contain variables. If a value for a variable makes an equation true, that value is a solution of the equation. s + 15 = 27 s = 12 12 + 15 s = 10 27 s = 12 is a solution because 12 + 15 = 27. 10 + 15 27 s = 10 is not a solution because 10 + 15 27.

Reading Math The symbol means “is not equal to. ”

Example 1: Determining Solutions of Equations Determine whether the given value of the variable is a solution. b — 447 = 1, 203 for b = 1, 650

Example 2: Determining Solutions of Equations Determine whether the given value of the variable is a solution. 27 x = 1, 485 for x = 54

Example 3 Determine whether the given value of the variable is a solution. A. u + 56 = 139 for u = 73

Example 4 Determine whether the given value of the variable is a solution. B. 45 = 100 - v for v = 55

Example 5 Determine whether the given value of the variable is a solution. C. 26 x = 13 for x = 2 26 × 2 = 52, not 13; 2 is not a solution.

Reading Math An equation has an equal sign, but an expression does not. An equation can be solved, but an expression can only be evaluated or simplified.

Real-World Application: Example 6 Determine whether the given value of the variable is a solution. Anna says that the table is 7 feet long. John says that the table is 84 inches long. Determine if these two measurements are equal.

Real-World Application: Example 7 Determine whether the given value of the variable is a solution. Ten Museum Park is a skyscraper in Miami, Florida. It is 585 feet tall. Jerry says that its height is 195 yards. Is Jerry correct?

Real-World Application: Example 8 Determine whether the given value of the variable is a solution. Ralph pays $2 for an individual slice of Pizza. He can buy the entire 8 -slice pizza for $12. Is this what he would pay for 8 individual slices?