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Inequality: A mathematical sentence that uses and inequality symbol (< , >, ≤, ≥) to compare the values of two expressions. . 3.3 Solving Inequalities Using: × and ÷. Solution of an Inequality: Any number that makes the inequality true. . GOAL:. MULTIPLICATION: ( x ).
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Inequality: A mathematical sentence that uses and inequality symbol (< , >, ≤, ≥) to compare the values of two expressions. 3.3 Solving Inequalities Using: × and ÷ Solution of an Inequality: Any number that makes the inequality true.
MULTIPLICATION: ( x ) Let a, b, and c be real numbers and c > 0 (positive). If a > b, Then ac > bc Ex: if 2 > -1 then 2(3) > -1(3) 6 > -3 If a < b, Then ac < bc Ex: if -4 < -2 then -4(3) < -1(3) -12 < -3
MULTIPLICATION: We can use these properties to solve for variables. Ex: What are the solutions to:
SOLUTION: To find the solution we must isolate the variable: given (8)(8) inverse of division c c > 2
YOU TRY IT: Ex: What are the solutions to:
SOLUTION: To find the solution we must isolate the variable: given (3)(3) inverse of division c
MULTIPLICATION: ( x ) Let a, b, and c be real numbers andc< 0 (negative). If a > b, Then ac < bc sign switches Ex: if 2 > -1 then 2(-3) < -1(-3) -6 < 3 If a < b, Then ac > bc sign switches Ex: if -4 < -2 then -4(-3) > -1(-3) 12 > 3
MULTIPLICATION: Once again, we can use these properties to solve for variables. Ex: What are the solutions to: http://www.khanacademy.org/math/algebra/linear_inequalities/inequalities/v/inequalities-using-multiplication-and-divisionhttp://www.khanacademy.org/math/algebra/linear_inequalities/inequalities/v/inequalities-using-multiplication-and-division
SOLUTION: To find the solution we must isolate the variable: given (-2)(-2) inverse of division n sign switches
YOU TRY IT: Ex: What are the solutions to:
SOLUTION: To find the solution we must isolate the variable: given (-2)(-2) inverse of division V sign switches
DIVISION: ( ÷ ) Let a, b, and c be real numbers and c > 0 (positive). If a > b, Then > Ex: if 4 > 2 then > 2 > 1 If a < b, Then < Ex: if -4 < -2 then < -2 < -1
YOU TRY IT: Ex: What are the solutions to:
SOLUTION: To find the solution we must isolate the variable: given inverse of multiplication x
DIVISION: ( ÷ ) Let a, b, and c be real numbers andc> 0 (negative). If a > b, Then <sign switches Ex: if 4 > 2 then > -2 < -1 If a < b, Then > sign switches Ex: if -4 < -2 then < 2 > 1
YOU TRY IT: Ex: What are the solutions to:
SOLUTION: To find the solution we must isolate the variable: given inverse of multiplication x sign switches
Real-World: You walk dogs in your neighborhood after school. You earn $4.50 per dog. How many dogs do you have to walk to earn at least $115?
SOLUTION: Data: $4.40 per dogx = number of dogs At least more than $4.50x > $115 Inverse of multiplication. > X > 25.5 dogs walk at least 26 dogs.
REMEMBER: Always isolate variables and then graph. x < -1 x > 1 x ≤ 0 x ≥ 2
VIDEOS: InequalitiesMultiplication/Division https://www.khanacademy.org/math/algebra/linear_inequalities/inequalities/v/inequalities-using-multiplication-and-division
CLASSWORK:Page 181-183 Problems: As many as needed to master the concept.