(((20點!!!急求救))求P的y坐標
回答 (4)
2008-10-12 10:43 pm
AB直線方程式 : (y-y1) / (x -x1) = (y2-y1) / (x2-x1)
(y-0) / (x-3) = [0-(-6)] /[3-(-1)]
y/(x-3) = 6 /4 = 3 /2
2y = 3x - 9
2y-3x+9=0
代入Px坐標 x = -7/3
2y-3(-7/3)+9 =0
2y+7+9 =0
2y = -16
y = -8
P的y坐標 = -8
(y-0) / (x-3) = [0-(-6)] /[3-(-1)]
y/(x-3) = 6 /4 = 3 /2
2y = 3x - 9
2y-3x+9=0
代入Px坐標 x = -7/3
2y-3(-7/3)+9 =0
2y+7+9 =0
2y = -16
y = -8
P的y坐標 = -8
2008-10-12 10:42 pm
Gradient of AB= 0-(-6) / 3-(-1) = 1.5
Y-intercept= -3*1.5 = -4.5
Formular of AB = Y=1.5x-4.5
Substitute x=-7/3 into the formular,
Y=1.5(-7/3)-4.5
Y=-8
therefor P's y-value is -8
Y-intercept= -3*1.5 = -4.5
Formular of AB = Y=1.5x-4.5
Substitute x=-7/3 into the formular,
Y=1.5(-7/3)-4.5
Y=-8
therefor P's y-value is -8
參考: mmmmmmmmmmeeeeeeeeeeeeee
2008-10-12 10:37 pm
Gradient of AB= 0-(-6) / 3-(-1) = 1.5
Y-intercept= -3*1.5 = -4.5
Formular of AB = Y=1.5x-4.5
Substitute x=-7/3 into the formular,
Y=1.5(-7/3)-4.5
Y=-8
therefor P's y-value is -8
Y-intercept= -3*1.5 = -4.5
Formular of AB = Y=1.5x-4.5
Substitute x=-7/3 into the formular,
Y=1.5(-7/3)-4.5
Y=-8
therefor P's y-value is -8
參考: me
收錄日期: 2021-04-13 16:09:44
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