Answer: it is 3 • (x + 4)
Step-by-step explanation: We move all terms to the left:
4-2x+8-(+5x)=0
We add all the numbers together, and all the variables
-2x-(+5x)+12=0
We get rid of parentheses
-2x-5x+12=0
We add all the numbers together, and all the variables
-7x+12=0
We move all terms containing x to the left, all other terms to the right
-7x=-12
x=-12/-7
x=1+5/7We move all terms to the left:
4-2x+8-(+5x)=0
We add all the numbers together, and all the variables
-2x-(+5x)+12=0
We get rid of parentheses
-2x-5x+12=0
We add all the numbers together, and all the variables
-7x+12=0
We move all terms containing x to the left, all other terms to the right
-7x=-12
x=-12/-7
x=1+5/7
Complete question :
Mr. Nelson lost one of his students' test papers. He knows that the other 4 students scored as follows: 60, 62, 56, 57. He also knows that the average score is 59.2. What is the score on the missing paper?
Answer:
61
Step-by-step explanation:
Given the following :
Total number of students = 4 + 1 missing = 5
Score on the four avaliable papers = 60, 62, 56, 57
Average score of the 5 papers = 59.2
Score on missing paper :
Sum of each score / number of papers
Sum of each score = sum of available scores + missing score
Let missing score = m
(60 + 62 + 56 + 57 + m) = 235 + m
Recall:
Average = total sum / number of observations
Hence,
59.2 = (235 + m) / 5
59.2 × 5 = 235 + m
296 = 235 + m
m = 296 - 235
m = 61
Missing score = 61
Answer:
4
Step-by-step explanation:
The distance between the two points is (-1,-4) - (-5,-4)
The sum of two numbers:
x + y = 108
The difference of the same two numbers:
x - y = 78
We can use substitution to figure out x and y:
x - y = 78 can be changed to x = 78 + y
We can plug this into the first equation:
78 + y + y = 108
78 + 2y = 108
2y = 30
y = 15
Now solve for x using any of the two equations. I'll use the first equation since it's easier:
x + 15 = 108
x = 93
