Answer:
Given 7b²-21b-273=7, the solutions are x1 = 8 and x2 = -5.
Step-by-step explanation:
Given 7b²-21b-273=7, first you need to equal zero. So
7b²-21b-273-7=0 ⇒ 7b²-21b-280 = 0
The secon step is to find the solutions applying Bhaskara´s formula x = (-b ± √(b²-4×a×c))/2×a
Where a=7, b= -21 and c= -280
After you identified each term, you have to replace it on the formula so....
x = (21 ± √(21² - 4×7×(-280)))/2×7 ⇒ x = (21 ± √(441 + 7840))/14 ⇒ x = (21 ± √8281)/14
Then you will obtain two values for x, called x1 = 8 and x2=-5.
Answer: 265720.5
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.
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(81^3) / 2 = 265720.5
A is the correct answer because it is the only one that shows the angles that add up to 180 degrees on a line since a supplementary angle is on the line and will add up to 180. D would be correct if angles 6,4,and7 were placed together as those angles together wake a line but no, this means A is the correct answer
A)...la suma de sus lados
