Question

2.   (8x-3) *(3x+2) -4x+7) *(x+4)= (2x+1)* (5x-1)

Answer 1

2. \(\left(8x-3\right).\left(3x+2\right)-\left(4x+7\right).\left(x+4\right)=\left(2x+1\right).\left(5x-1\right)\)

\(\Leftrightarrow24x^2+16x-9x-6-4x^2-16x-7x-28=10x^2-2x+5x-1\)

\(\Leftrightarrow20x^2-16x-34=10x^2+3x-1\)

\(\Leftrightarrow10x^2-19x-33=0\)

\(\Leftrightarrow\left(x-3\right).\left(x+\frac{11}{10}\right)\)

\(\Leftrightarrow\orbr{\begin{cases}x=3\\x=-\frac{11}{10}\end{cases}}\)

( Đúng thì ) hihi