No Calculator, No Problem (Just Kidding!🤣)
What is an expression?
A math phrase with numbers, variables, and operations (no equal sign).
What is an equation?
A math sentence with an equal sign.
What is an inequality?
A math sentence using <, >, ≤, or ≥ instead of =.
What is a variable?
A letter that stands for a number.
You have $20. You spend $x on snacks. Write an expression for how much money you have left.
20 − x
In 3x + 7, what is the coefficient?
3
Solve: x + 4 = 9.
x = 5
Solve: x + 2 < 5
x < 3
What is the constant term in 7x + 5?
5
A movie ticket costs $10. Write an inequality for how many tickets you can buy with $50.
10x ≤ 50
In 5y − 2, what is the constant?
-2
What does it mean when we say two sides of an equation are balanced?
They have the same value.
When do you flip the inequality sign?
When multiplying or dividing by a negative.
What is a coefficient?
The number multiplied by a variable.
Write an equation: “Five more than twice a number is 15.”
2x + 5 = 15
Simplify: 2x + 3x.
5x
Solve: 2x − 3 = 7.
x = 5
Solve: −3x > 6.
x < −2
What’s the difference between an equation and an expression?
Equation has an equal sign; expression does not.
A gym membership costs $30 per month. Write an expression for the cost of m months.
30m
What does it mean to evaluate an expression?
Replace the variable with a number and solve.
What do you call a number that makes an equation true?
A solution.
Draw the solution to x ≥ 4 on a number line.
Closed circle on 4, shade right.
What is a solution set?
All values that make the equation or inequality true.
A test requires a score of at least 70 to pass. Write an inequality for the score s.
s ≥ 70