unit 1.7  Algebraic equations (First grade)
what do we need to know?
 Parts of an algebraic expression: terms, coefficients, variables, constant.
 Difference between expressions and equations: the equal sign.
 "To write an algebraic equation" means to assign a variable, and to identify the constant.
 To solve an equation means to find out the value of the variable.
 There are different ways to solve equations.
 Difference between expressions and equations: the equal sign.
 "To write an algebraic equation" means to assign a variable, and to identify the constant.
 To solve an equation means to find out the value of the variable.
 There are different ways to solve equations.
class notes


more information
What is an equation?
An equation is one quantity equal to another quantity. Each of the quantities may be a number or an algebraic expression. A couple of things to be aware of:
 The VARIABLE represents a specific unknown value.
 Each side of the equation has the same value.
Here are some examples:
 The VARIABLE represents a specific unknown value.
 Each side of the equation has the same value.
Here are some examples:
 To solve these equations means to find the value of X and the value of r by doing arithmetic operations.
 We will get into this in a little later, but your goal is to END WITH A POSITIVE VARIABLE THAT HAS A COEFFICIENT OF 1 on one side, and a numerical value on the other side of the equal sign.. 
 These equations are called first grade equations because there is only one variable in each of them.
 In the equation on the left: Variable = X Coefficient =3 Constant = 5  In the equation above: Variable = r Coefficient = 3 Constant = 8 
Furthermore:
This equation reads:
"3 times a number plus five equals 17" ("a number" is the variable x)
"3 times a number plus five equals 17" ("a number" is the variable x)
This equation reads:
" 3 times a number added to 7 equals 8."
" 3 times a number added to 7 equals 8."
putting words into equations
Here are some of the things that will hopefully help you:
 Anytime you see "a number", know that it means the variable (and you can give assign it whatever letter). It makes sense if you think about it: "a number" means any number, and since the value is not set, this refers to a variable.
 4d is 4xd. When a letter and a number are together and there isn't anything between them, MULTIPLICATION is the implied operation.
 2s can be written as "two times a number", or DOUBLE a number.
 3x can be written as "three times a number", or TRIPLE a number.
 Anytime you see "a number", know that it means the variable (and you can give assign it whatever letter). It makes sense if you think about it: "a number" means any number, and since the value is not set, this refers to a variable.
 4d is 4xd. When a letter and a number are together and there isn't anything between them, MULTIPLICATION is the implied operation.
 2s can be written as "two times a number", or DOUBLE a number.
 3x can be written as "three times a number", or TRIPLE a number.
 "SQUARED" means with an exponent of 2, raised to the power of 2.
 "CUBED" means with an exponent of 3, raised to the power of 3.
 In my experience, the following is where we make the most mistakes. Take a look at these two seemingly equal expressions:
3x  8 > 8 SUBTRACTED from 3 times a number OR 3 times a number minus 8.
8  3x > 8 minus 3 times a number OR three times a number SUBTRACTED from 8.
In other words:
 If you name the first term (8 and ex), then you can use "minus." If you name the second term first, you must used SUBTRACTED FROM.
3x  8 > 8 SUBTRACTED from 3 times a number OR 3 times a number minus 8.
8  3x > 8 minus 3 times a number OR three times a number SUBTRACTED from 8.
In other words:
 If you name the first term (8 and ex), then you can use "minus." If you name the second term first, you must used SUBTRACTED FROM.
useful vocabulary
EXAMPLES OF EQUATION WRITING
videos that may help
online interactive activities
worksheets







review  workbook
math_7__workbook__unit_1.7.pdf  
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