* \(2x\left(12x-5\right)-8x\left(3x-1\right)=30\Leftrightarrow24x^2-10x-24x^2+8x=30\) \(\Leftrightarrow-10x+8x=30\Leftrightarrow-2x=30\Leftrightarrow x=\dfrac{30}{-2}=-15\) vậy \(x=-15\)
* \(3x\left(3-2x\right)+6x\left(x-1\right)=15\Leftrightarrow9x-6x^2+6x^2-6x=15\)
\(\Leftrightarrow9x-6x=15\Leftrightarrow3x=15\Leftrightarrow x=\dfrac{15}{3}=5\) vậy \(x=5\)
a, \(2x\left(12x-5\right)-8x\left(3x-1\right)=30\)
\(24x^2-10x-24x^2+8x=30\)
\(\left(24x^2-24x^2\right)-\left(10x-8x\right)=24\)
\(-2x=24\)
\(x=-12\)
b, \(3x\left(3-2x\right)+6x\left(x-1\right)=15\)
\(9x-6x^2+6x^2-6x=15\)
\(\left(9x-6x\right)+\left(-6x^2+6x^2\right)=15\)
\(3x=15\)
\(x=5\)
\(\text{a) }2x\left(12x-5\right)-8x\left(3x-1\right)=30\\ \Leftrightarrow24x^2-10x-24x^2+8x=30\\ \Leftrightarrow\left(24x^2-24x^2\right)-\left(10x-8x\right)=24\\ \Leftrightarrow-2x=24\\ \Leftrightarrow x=-12\\ \text{Vậy }x=-12\\ \\ \)
\(\text{b) }3x\left(3-2x\right)+6x\left(x-1\right)=15\\ \Leftrightarrow9x-6x^2+6x^2-6x=15\\ \Leftrightarrow\left(9x-6x\right)-\left(6x^2-6x^2\right)=15\\ \Leftrightarrow3x=15\\ \Leftrightarrow x=5\\ \text{Vậy }x=5\)
a, 2x(12x-5)-8x(3x-1)=30
=>24x2-10x-24x2+8x=30
=>-2x=30
=>x=15
b, 3x(3-2x)+6x(x-1)=15
=>9x-6x2+6x2-6x=15
=>3x=15
=>x=5
à, mấy bài dạng này, thường thì bạn cứ biến đổi vế phức tạp ( tính bung ra ) rồi nhóm lại cho gọn là ra dạng tìm x lớp 5 thôi
\(2x\left(12x-5\right)-8x\left(3x-1\right)=30\)
\(\Leftrightarrow24x^2-10x-24x^2+8x=30\)
\(\Leftrightarrow\left(24x^2-24x^2\right)-\left(10x-8x\right)=30\)
\(\Leftrightarrow-2x=30\)
\(x=30+\left(-2\right)\)
x = -15
b) \(3x\left(3-2x\right)+6x\left(x-1\right)=15\)
\(\Leftrightarrow9x-6x^2+6x^2-6x=15\)
\(\Leftrightarrow\left(-6x^2+6x^2\right)+\left(9x-6x\right)=15\)
\(\Leftrightarrow3x=15\)
x = 15 : 3
x = 5
a) 2x(12x–5) – 8x(3x-1) = 30 b)
=> 2x.12x – 2x.5 2x – 8x.3x + 8x.1 = 30
=> 24x2 – 10x – 24x2 + 8x = 30
=> -10x + 8x = 30
=> -2x = 30
=> -x = 15
=> x = -15
