10 students averaged 80, so the sum of their scores was (10 x 80) = 800
20 students averaged 89, so the sum of their scores was (20 x 89) = 1,780
All together, the sum of all 30 scores was (800 + 1,780) = 2,580
30 students totaled 2,580, so their average was (2,580 / 30) = <em> 86</em> .
Answer:
Step-by-step explanation:
Declaration
Let Heather's number of messages = x
Let Eric's number of messages = x + 9
Let Chang's number of messages = 3(x +9)
Equation
x + x + 9 + 3(x + 9) = 116
Solution
x + x + 9 + 3(x + 9) = 116 Remove the brackets
x + x + 9 + 3x + 27 = 116 Combine like terms
x + x + 3x + 9 + 27 = 116
5x + 36 = 116 Subtract 36 from both sides
5x + 36 - 36 = 116 - 36 Combine
5x = 80 Divide both sides by 5
5x/5 = 80/5
x = 16
Answer
Heather = 16
Eric = 16 + 9 = 25
Chang = 3*25 = 75
Plug in the values of p and q where you see them in the equation:
-(2+4)2 / (-6) - Distribute the -1
(-2-4)2 / (-6) - Distribute the 2
(-4-8) / (-6) - Subtract what's inside the parenthesis
(-12) / (-6) - Divide
The answer is 2
The +2 goes on the Y-Axis… From
the 2 count up 3 times and go to the right 2 times
The length, width, and height In the most common contexts in elementary school, mathematics does not have a formal definition for these terms, nor does it have rules about "proper" use.
