Answer: no not less than 23
David's score on his fifth test would be an 87. If you add up all the scores from his first to his fourth test, it would 363. However, since there are five tests, in order to get a 90 percent, the sum of all five test scores would be 450. 450 - 363 = 87.
Step-by-step explanation:
For no 1...
The range is [ -9, -7, 1]
For no 2....
The range is [-12, -10, -2]
For no 3.....
The range is [-11, -8, 4]
LCM 14 & 24 = 168
then use the highest exponents for the variables
answer = 168x^6y^6z^8
Y = 7x^2-3
x=7y^2-3
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