[問題]GWD-5-26

[Grace]

Q26:
In the xy-plane, the line with equation ax + by + c = 0, where abc ≠ 0, has slope . What is the value of b?
(1) a = 4
(2) c = −6



Ans: A.

請問這題是考什麼觀念?? Help~

[homaru]

In the xy-plane, the line with equation ax + by + c = 0, where abc ≠ 0, has slope2/3 . What is the value of b?
ax+by+c=0
by=-ax-c
y=(-a/b)x-c/b
有斜率2/3
so -a/b=2/3
條件(1)代入即可

ps.word裡的分數也是,貼上會看不見,要自己重打

[Grace]

喔我懂了....原來要先將ax+by+c=0 化簡為Y=(-a/b)x-c/b
I got it...Thanks for your soonest response. :P