Question

Tìm x biết : (4x+3)(4x-3)-(4x-5)^2=46

Answer 1

\(\left(4x+3\right)\left(4x-3\right)-\left(4x-5\right)^2=46\)

\(\Leftrightarrow16x^2-9-\left(16x^2-40x+25\right)=46\)

\(\Leftrightarrow16x^2-9-16x^2+40x-25=46\)

\(\Leftrightarrow40x-34=46\Leftrightarrow40x=80\Leftrightarrow x=2\)

Answer 2

x= 2 bấm máy tính là tự ra à