更新1:
can someone explain the rule behind the "<" sign? i just want to understand why the answer is >-3 and not -3. thanks in advance!
Can you solve :2/3 Q + 5 < 2Q+ 9?
回答 (4)
2009-05-06 5:10 pm
✔ 最佳答案
-4 < 4/3qq > -3
2009-05-06 5:24 pm
2/3q+5<2q+9
take 5 and 2q on the other sides respectively
2/3q-2q<9-5
-4/3q<4
take 3 the other side n multiply
-4q<12
divide by -4 on both sides and so sign of equality also changes
q>-3
take 5 and 2q on the other sides respectively
2/3q-2q<9-5
-4/3q<4
take 3 the other side n multiply
-4q<12
divide by -4 on both sides and so sign of equality also changes
q>-3
2009-05-06 5:12 pm
2/3Q + 5 < 2Q + 9
_times each side by 3
2Q + 15 < 6Q + 27
_minus 2Q from both sides
15 < 4Q + 27
_minus 27 from both sides
-12 < 4Q
_divide both sides by 4
-3 < Q
THATS THE ANSWER
_times each side by 3
2Q + 15 < 6Q + 27
_minus 2Q from both sides
15 < 4Q + 27
_minus 27 from both sides
-12 < 4Q
_divide both sides by 4
-3 < Q
THATS THE ANSWER
2009-05-06 5:11 pm
2/3(Q) + 5 < 2Q + 9
2Q/3 + 5 < 2Q + 9
2Q/3 - 2Q < -5 + 9
2Q(1/3 - 1) < 4
2Q > 4/(1/3 - 3/3)
2Q > 4/(-2/3)
Q > [4(-3/2)]/2
Q > (-6)/2
Q > -3
2Q/3 + 5 < 2Q + 9
2Q/3 - 2Q < -5 + 9
2Q(1/3 - 1) < 4
2Q > 4/(1/3 - 3/3)
2Q > 4/(-2/3)
Q > [4(-3/2)]/2
Q > (-6)/2
Q > -3
收錄日期: 2021-05-01 12:21:28
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20090506090614AAXGAc2