Algebra Equations Lesson 1-7 Pages 49-52

Equations An Equation is a sentence that contains an equals = sign. The equals = sign tells you that the expression on the left is equivalent to the expression (or value) on the right. 7 = 8 – 1 3(4) = =

Equations with Variables An equation with a variable is neither true or false until the variable is replaced with a number. A solution of an equation is a numerical value for the variable that makes the sentence true. 18 = 14 + t(write the equation) 18 = (use math logic to solve) 18 = 18(balance the equation) (simplify) *SOLVING AN EQUATION – Steps listed above.

Defining a variable When you choose a variable to represent one of the unknowns, it is called defining the variable. – Example: The totale cost of a hamburger and a soft drink is $5.50. If the drink costs $2.50, what is the cost of the hamburger? *(Let h = the cost in $ of the hamburger) h = 5.50 *(here we defined h as the variable)

Practice problems Page 51 #6-28