Equations and Expressions
Whats the difference between an equation and an expression?
An expression is a number, a variable, or a combination of numbers and variables, and operation symbols. An equation is made up of two expressions connected by an equal sign.
What is a variable?
a quantity that may change within the context of a mathematical problem or experiment.
50-21
29
What does GEMDAS stand for?
Groupings
Exponents
Multiplication
Division
Addition
Subtraction
7 subtracted from a number divided by 10
(N-7)/10
k cannot be a variable in an expression or equation
True or False
False, usually x is the variable in an equation but any letter can be used as a variable
In a zoo, there were 36 exhibits, but š exhibits were closed. Write the expression for the number of exhibits that were open
36-k
8/4
2
What does PEMDAS stand for?
Parentheses
Exponents
Multiplication
Division
Addition
Subtraction
the sum of a number and 8
N + 8
Are a math sentence and an equation the same thing?
yes, an equation is a math sentence (an expression is not)
In Charlotteās sewing kit, there are š” bundles of thread. Each bundle has 34 feet of thread. Write the expression for the total length of the thread in her sewing kit.
34t
9-8
1
(2+10)3 - 7
29
5 less than a number g is 15
write out the equation and solve for g
G - 5 = 15
G = 20
An expression has to have an equal sign (=)
NO, an equation has to have an equal sign
4x + 3 = 7
find x.
x=1
23
8
2(3) + 50 - 4(9)
20
a number plus 10 divided by 2
(N + 10)/2
2x + 4(53x) - 4(5-2)
4(8) + 2x - (8-7) = 4x
Which one of these problems is an equation?
2
A piece of ribbon is š¦ cm long. Ashley cut it into 4 equal pieces to do her 4 sistersā hair. Write the expression for the amount of ribbon used for each sister.
š¦/4
2+2
4
23(4) - 5
27
N/6