Step-by-step explanation:
the question is not correct
edit it and I will answer u in comments
B² = 8b + 84
b² - 8b - 84 = 0
b = <u>-(-8) +/- √((8)² - 4(1)(-84))</u>
2(1)<u>
</u>b = <u>8 +/- √(64 + 336)</u>
2
b = <u>8 +/- √(400)
</u> 2<u>
</u>b = <u>8 +/- 20
</u> 2
b = 4 <u>+</u> 10
b = 4 + 10 b = 4 - 10
b = 14 b = -6
<u />
27) if a = 1/a
multiply both sides by a
a * a = 1/a * a
a^ 2 = 1
Answer is D) 1
28)
6 x 75 = 450
7 x 80 = 560
8 x 85 = 680
9 x 90 = 810
Total all students in class = 6 + 7 + 8 + 9 = 30 students
Total score of whole class:
450 + 560 + 680 + 810 = 2500
Average = 2500 /30 = 83.3 = 83 1/3
Answer is C) 83 1/3
The manager’s likely error was forgetting to add the $2 back to the $18. Because $2 is roughly 11% of $18 for a markup you need to add the $2 back into the $18 for a total of $20.
