Exponents
Write variable expression represents the number of inches in y yards? (page 162 #1)
A) 36y or B) y/36 or C) 36-7
a) 36y
What is the value of the expression 15-14 ÷ 2 + 5?
13
This is a PEMDAS problem. Use parenthesis and subtraction is adding a negative to help you see that you have to divide -14 by 2 first
15 + (-14/2) + 5 = 15 - 7 + 5
Then use subtraction is adding a negative so you can move terms around if they are all addition
15 + (-7) + 5 = 15 + 5 + (-7) = 20 - 7 = 13
Write a(b+c) in expanded form. BONUS: What's the name of this property?
ab + ac
The distributive property
x + 7 = 21
x = 14
x + 7 - 7 = 21 -7
Solve
y+11<23
Answer
y<12
y+11<23
y+11-11<23-11 (use inverse operations on both sides to isolate the variable)
y<12
During January, the average high temperature in Montreal, Canada is -6 degrees C and the average low temperature is -15 degrees C. How much greater is the average high temperature than the average low temperature?
|-15| - |-6| = 15 - 6 = 9
Draw a coordinate plane and graph (1, -2). Which quadrant is it in?
Quandrant II
Which expression is equivalent to 3(0.9 +7)?
A) 3(0.9) + 7 B) 0.27 + 21 C) 3(0.9) + 3(7) D) 2.7 + 7
C) 3(0.9) + 3(7)
Why is B) 0.27 + 21 incorrect?
25x = 100
x =4
(25x)/25 = 100/25
x = 4
Solve
3-8x=-141
x=18
What is the base of 2^7 What does the exponent 7 mean?
The base is 2. 7 means how many times the base is used as a factor
Which terms of the expression 4x + 9 + 9x - 4 are like terms?
4x and 9x
Solve
5x>30
(5x)/5>30/5
x>6
Solve
3>a/-9
Answer -27 < a or a>-27
3>a/-9
(3)(-9)<(a/-9)(-9) reverse the inequality sign
Write this as repeated multiplication then solve
(0.2)^5
(0.2)(0.2)(0.2)(0.2)(0.2)=0.00032
Solve 10 + x = -19
-29
10 - 10 + x = -19 -10
x = -19 + -10 = -29
What is the solution of the inequality
-3x+14>2x-11
Answer: x<5
-3x+14>2x-11 move all constants to one side
-3x +14-14>2x-11-14
-3x-2x>2x-2x-11+-14 subtraction is adding a negative
-3x+-2x>-25
-5x>-25 combine like terms
(-5x)/-5<-25/-5 reverse the inequality
x<5
simplify (or which expression is equivalent to)
8(x+2) - 5(x-3)
8(x+2) - 5(x-3)
8x + 16 +[ -5(x-3)]
8x + 16 + -5x +15
8x +-5x +16 +15
3x + 31
A soccer goalie has made 175 saves so far this season. The school record is 236 saves in a season. There are 6 games left to play. Write an inequality you could solve to find the average number of saves the goalie must make in the remaining games to BREAK the school record.
175 + 6x>236
Find the solution of
-4x-5<7
-4x-5 +5 <7+5
-4x<12
(-4x)/-4>12/-4
x>-3