\(a.4x\left(x-5\right)-\left(x-1\right)\left(4x-3\right)=5\)
\(4x^2-20x-\left(4x^2-3x-4x+3\right)=5\)
\(4x^2-20x-4x^2+3x+4x-3=5\)
\(-13x-3=5\)
\(-13x=8\)
\(x=-\dfrac{8}{13}\)
Vậy \(x=-\dfrac{8}{13}\)
a,4x(x-5)-(x-1)(4x-3)=5
=>4x2-20x-(4x2-3x)+(4x-3)=5
=>4x2-20x-4x2+3x+4x-3=5
=>(4x2-4x2)-(20x-3x-4x)-3=5
=>-13x-3=5
=> -13x=8
=>x=\(\dfrac{-8}{13}\)
Vậy x=\(\dfrac{-8}{13}\)
\(b.\left(x-5\right)\left(x-4\right)-\left(x+1\right)\left(x-2\right)=7\)
\(x^2-4x-5x+20-\left(x^2-2x+x-2\right)=7\)
\(x^2-4x-5x+20-x^2+2x-x+2=7\)
\(-8x+20+2=7\)
\(-8x=-15\)
\(x=\dfrac{15}{8}\)
Vậy \(x=\dfrac{15}{8}\)
\(c.\left(2x-1\right)\left(x-2\right)-\left(x+3\right)\left(2x-7\right)=3\)
\(2x^2-4x-x+2-\left(2x^2-7x+6x-21\right)=3\)
\(2x^2-4x-x+2-2x^2+7x-6x+21=3\)
\(-4x+2+21=3\)
\(-4x=-20\)
\(x=5\)
Vậy \(x=5\)
\(d.6\left(x-3\right)\left(x-4\right)-6x\left(x-2\right)=4\)
\(\left(6x-18\right)\left(x-4\right)-6x^2+12x=4\)
\(6x^2-24x-18x+72-6x^2+12x=4\)
\(-30x+72=4\)
\(-30x=-68\)
\(x=\dfrac{34}{15}\)
Vậy \(x=\dfrac{34}{15}\)
