Positive & Negative Numbers
True or False: A temperature below zero is represented by a positive number.
False
What is the opposite of 5?
-5
What is the opposite of -6?
6
What are the four sections of the coordinate plane called?
Quadrants
What is the point called that represents zero on a number line?
The origin
The temperature is -3°F in the morning and rises 5°F by noon. What is the new temperature?
2°F
Plot -3 on a number line. Which direction from zero is it?
Left
On a number line, how far apart are a number and its opposite?
Twice the distance from zero
What are the coordinates of a point 3 units right and 2 units up from the origin?
(3,2)
What is a ratio?
A comparison of two quantities using division
Write a situation where you’d use a negative number in real life.
Answers vary (examples: depth below sea level, loss of money, temperature below 0°F)
Which two numbers are the same distance from zero: -8 or 8?
Both — they are opposites
The opposite of a number is 9. What is the original number?
-9
Which quadrant contains points with a negative x-value and positive y-value?
Quadrant II
Write the inequality: –4 ___ –1
–4 < –1
A submarine is at -250 feet. It rises 180 feet. What is its new depth?
-70 feet
Which number is greater: -4 or -9?
-4
Explain how 4 and -4 are related.
They are opposites and the same distance from zero in opposite directions
What is the opposite of the point (4, -5)?
(-4, 5)
A recipe calls for 4 cups of water for every 2 cups of rice. What is the ratio of water to rice?
4:2 or 2:1
4/2 or 2/1
4 to 2 or 2 to 1
Explain what zero represents on a number line that shows elevations.
Sea level — neither above nor below sea level
If point A is at -2 and point B is at 5, what is the distance between them?
7 units
Write two numbers that are opposites of each other and describe a real-world example.
Answers vary (examples: +10 and -10 for winning or losing $10)
A point is reflected across both axes. Its original coordinates are (-7, 3). What are the new coordinates?
(7, -3)
Order the numbers from least to greatest: –8, –2, 0, 4.
–8, –2, 0, 4