Answers:
bio = 258
sociology = 169
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Work Shown:
x = number of bio textbooks
y = number of sociology textbooks
x+y = 427 books sold total
y = x-89 since 89 less sociology textbooks were sold compared to bio
Apply substitution to get the following
x+y = 427
x+x-89 = 427 ... replace y with x-89
2x-89 = 427
2x = 427+89
2x = 516
x = 516/2
x = 258 bio textbooks were sold
y = x-89
y = 258-89
y = 169 sociology textbooks were sold
<h2>
Coordinate of mid point = (1,0)</h2>
Step-by-step explanation:
Given points are (-6,3) and (4,-3)
,
and 
Coordinate of mid point 

=(1,0)
In case A, as the error would be a difference of 1, the assumption could be mantained, but in case B the difference will be bigger, showing that the ratio is not 3:1 but 4:1.
<h3><u>Ratios</u></h3>
Given that a preliminary study was carried out to test the hypothesis that the ratio of white to dark herons on the island was 3:1, but A) a small census found 16 white morphs and 4 dark, to determine if the assumption of a 3 :1 ratio could be rejected, and B) to determine the same question if the census were larger with 160 white morphs and 40 dark, the following calculations must be made:
A)
- 3 + 1 = 4
- 16 + 4 = 20
- 4 = 20
- 3 = X
- 60 / 4 = X
- 15 = X
- Therefore, as the error would be a difference of 1, the assumption could be mantained.
B)
- 3 + 1 = 4
- 160 + 40 = 200
- 150 = 3:1
- In this case, the difference will be bigger, showing that the ratio is not 3:1 but 4:1.
Learn more about ratios in brainly.com/question/1504221
You can double the product of 9 and 4 to get to the product of 9 and 8
Answer:
a: x − 2y = −12
Step-by-step explanation:
the standard form of a line is is usually given as Ax + By = C, so just by deduction you can tell that the correct answer is a.
If you want to do the procedure it would be:
y − 3 = 1/2 (x + 6)
y − 3 = 1/2 x + 3
y - 1/2 x = 3 + 3
y - 1/2 x = 6
(y - 1/2 x = 6) * 2 to get rid of the fraction
2y - x = 12 rearrenge the terms
x - 2y = -12