Quiz 7.1-7.4 Review
7.1 Writing Equations in One Variable
Writing equations:
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Equation – a mathematical sentence that uses = to show two expressions are equal.
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To write equation, look for words is, the same as, or equals, to place = .
Writing an equation from a word problem:
7.2 Solving Equations Using Addition or Subtraction
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Solution – a value that makes an equation true.
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Inverse operations – operations that “undo” each other .
Checking solutions:
Solving equations
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Use inverse operations to solve equations.
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Addition and subtraction are inverse operations.
Solving equations using addition:
Solving equations using subtraction:
Writing and solving an equation using addition/subtraction from a word problem:
7.3 Solving Equations Using Multiplication or Division
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Use inverse operations to solve equations.
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Multiplication and division are inverse operations.
Solving equations with multiplication:
Solving equations with division:
Writing and solving an equation using multiplication/division from a word problem:
7.4 Writing Equations in Two Variables
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Equation in two variables: two quantities that change in relation to each other
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Solution to an equation in two variables: an ordered pair that makes the equation true
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Independent variable: in a two variable equation, the variable whose value can change freely
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Dependent variable: in a two equation variable, the variable whose value depends on the
independent variable
Identifying solutions of equations in two variables:
Using an equation in two variables:
Writing and graphing an equation in two variables:
Distance formula: