13.5 Inequalities (p.300-303)

I. An inequality is an algebraic sentence that contains the symbol <, >, ≤, ≥, or ≠ because the sides are not equal
II. An inequality can sometimes be solved the same way as an equation
III. When graphing on a number line
A. <> Use an open circle if the value at that spot is not included in the solution
B. ≤ or ≥ Use a filled in circle if the value at that spot is a possible solution
IV. If you multiply both sides of an inequality by a negative number it will reverse the direction of the inequality sign

13.4 Problem Solving: Work Backwards (p.298-299)

13.4 Problem Solving: Work Backwards (p. 298-299)
I. Use when the problem describes a series of actions and tells the result
II. Can be used to solve a problem represented by an equation by undoing the operation
III. When a desired outcome is known, work backwards to figure out what you need to do to make it work

13.3 Use Formulas (p.294-297)

I. A formula is a rule or principle used to find a value: i.e. area, perimeter, volume, etc…
II. Use properties of equations to solve for the variable in a formula
III. Useful formulas:
Converting between Fahrenheit and Celsius :
F = (9/5 x C)+32
C = 5/9 x (F-32)
Average Speed: d = rt (distance equals rate times time)

13.1-2 Solve Multiplication and Division Equations (p.290-293)

I. Focus on getting the variable by itself on one side of the equation – use the opposite operation to cancel and balance the equation.
II. Division Property of Equality: If both sides of an equation are divided by the same nonzero number, the two sides remain equal
III. Multiplication Property of Equality: both sides of an equation are multiplied by the same number, the two sides remain equal.