求幫忙~~這題我不會?
回答 (2)
2017-04-04 2:21 pm
設ax^2+22x+15=(2x+3)(kx+15/3)
ax^2+22x+15=(2x+3)(kx+5)
代x=-3/2
a(-3/2)^2 +22(-3/2)+15=0
(9a)/4=18
a=8
(C)
ax^2+22x+15=(2x+3)(kx+5)
代x=-3/2
a(-3/2)^2 +22(-3/2)+15=0
(9a)/4=18
a=8
(C)
2017-04-04 12:52 pm
ax^2+22x+15=(2x+3)(bx+5) ----> b=4
=8x^2+22x+15 ----> a=8 .......Ans: (C)
=8x^2+22x+15 ----> a=8 .......Ans: (C)
收錄日期: 2021-04-18 16:06:31
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20170404023750AAUFr80