2x + 5 = 15
x=5
A movie ticket costs $9. Ben spent $36 on tickets. How many tickets did he buy?
36÷9=4. He bought 4 tickets.
Define "coefficient"
A coefficient is a number that multiplies a variable.
The output of the function f(x)=2x+3 when x=2
Output is 7
How many players are on a soccer team on the field at one time?
11
3(x−4)=9
x=7
Tom had $50. He spent $18.
How much money does he have left?
50−18=32. Tom has $32 left.
The term for a number that stands on its own in an expression or equation
Constant
Is this a function?
(1, 2), (2, 4), (3, 6), (4, 8)
Yes!
What is 25% of 200?
50
4x−7=2x+5
x=6
A number increased by 7 equals 15.
What is the number?
x=8 x + 7 = 15
The difference between an expression and an equation is
An expression does not have an equality sign, while an equation does.
If f(x)=2x+5
Find f(3)
f(3) = 11
What is the fastest land animal?
Cheetah
−2(x+3)+4=10
x=-6
Twice a number minus 4 equals 10.
What is the number?
2x−4=10 ⇒ 2x=14 ⇒ x=7 2x - 4 = 10
The number is 7.
The steepness of a line
Slope
Decide if it’s a function:
Each student has one school ID number.
Each student has more than one favorite food.
ID: Yes
Favorite Food: No
How many bones are in the adult human body?
206
5x+3=2(3x+1)
x=1
Sarah bought 3 notebooks. Each notebook costs $4. How much did she spend in total?
3×4=12. She spent $12.
Terms that have the same variable and exponent
Like Terms
A movie theater charges $10 per ticket. Write a function that shows the total cost (C) for buying x tickets.
C = 10x
In which year were the first modern Olympic Games held?
1896