Tìm x biết; 3( 5/3x -7) -2( 1.5x +6) -(5 -x) (x +4) = 80 + x^2 .
Giải thích
353x−7−21.5x+6−5−xx+4=80+x2
⇔ 353x−7−25x+6−5x−20+x2+4x=80+x2
⇔ 5x – 21 – 10x – 12 – 5x – 20 + x2 + 4x = 80 + x2
⇔ −5x – 20 + x2 + 4x = 80 + x2
⇔ −6x = 133
⇔ x=−1336.
353x−7−21.5x+6−5−xx+4=80+x2
⇔ 353x−7−25x+6−5x−20+x2+4x=80+x2
⇔ 5x – 21 – 10x – 12 – 5x – 20 + x2 + 4x = 80 + x2
⇔ −5x – 20 + x2 + 4x = 80 + x2
⇔ −6x = 133
⇔ x=−1336.