(x-2).(x+7)=(x-1).(x-4)
=> x . (x + 7) - 2(x + 7) = x(x-4) - (x - 4)
=> x2 + 7x - 2x + 14 = x2 - 4x -x + 4
=> x2 + 5x + 14 - 4 = x2 - 5x
=> x2 + 10 = x2 - 5x - 5x
=> x2 + 10 = x2 - 10x
=> -10 = 10x
=> x = -1
Bài 1 Tìm x
a, x-1/x+5=6/7(x khác 5)
b, x-2/x-1=x+4/x+7
Bài 2: Tìm x biết
x/y^2 và x/y=16
Bài 3: cho 3x=2y tính
x/y^2=y/2^x
Bài 4:tìm x
a,|x|+|x+2|=0
b,|x(x^2-5/4)|=x
c, (2x-5)^2000+(3y+4)^2000< hoặc = 0
các bạn ơi giúp mik với
a) (3x-5).(x+1)-(3x-1).(x+1)=x-4
b) (x-2).(x+3)-(x+4).(x-7)=5-x
c) 5.(x-3).(x-7)-(5x+1).(x-2)
d) 3.(x-7).(x+7)-(x-1).(3x+2)=13
tìm x
Tìm x:
1) (x-2)/(x-1) = (x+4)/(x-7)
2) (x+4)/20=5/(x+4)
Tìm x
a) x-3/x+5=5/7
b)7/x-1=x+1/9
c)x+4/20=5/x+4
d)x-1/x+2=x-2/x+3
Tìm x
a) x-3/x+5=5/7
b)7/x-1=x+1/9
c)x+4/20=5/x+4
d)x-1/x+2=x-2/x+3
. Tìm x, biết: a) (x - 3)/(5 - x) = 5/7 b) (x - 2)/(x - 1) = (x + 4)/(x + 7)
tìm x: (x-2)/(x-1)=(x+4)/(x+7)
Tìm x
a) x-1/7=9/x+1
b) x-2/x-1=x+4/x+7
Bài 1. Tìm \(x\).
a) -5(\(x\)2-3\(x\)+1)+\(x \)(1+5\(x\))=\(x-2\)
b) \(12x\)2\(-4x\)\((3x+5)\)\(=10x-17\)
c) \(-4x(x-5)+7x(x-4)-3x\)2\(=12\)
Bài 2. Tính ( Rút gọn).
a) \((x+5).(x-7)-7x.(x-3)\)
b) \(x.(x\)2\(-x-2)-(x-5).(x+1)\)
c) \((x-5).(x-7)-.(x+4).(x-3)\)
d) \((x-1).(x-2)-(x+5).(x+2)\)
tìm x biết
(x - 2) : (x - 1)= (x + 4) : (x + 7)
