Answer:
7n-20 I believe
Step-by-step explanation:
hope this helps
Answer:
x = 1 and y = -2
Step-by-step explanation:
Given that,
2x-3y = 8 ..(1)
4x+3y = -2 ..(2)
Add equation (1) and (2),
2x-3y+4x+3y = 8+(-2)
6x = 6
x = 1
Put the value of x in equation (1).
2-3y = 8
2-8 = 3y
-6 = 3y
y = -2
Hence, the value of x is 1 and that of y is -2.
9 x 15 = ( 9 x 9) + (9 x 15)
Answer:
2
Step-by-step explanation:
This implies
x+2=4
and
-(x+2)=-4.
x+2=4 implies x=2 since subtract 2 on both sides gives us x=2.
Solving -(x+2)=-4 should give us the same value.
Multiply both sides by -1:
x+2=4
It is the same equation as the other.
You will get x=2 either way.
Let's check:
Put both sides into your calculator and see if you get the same thing on both sides:
Left hand side gives 256/81.
Right hand side gives 256/81.
Both side are indeed the same for x=2.
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
