Question

(2*x+3)*(x+4)-(2 -3*x)*(x-7)

 

Answer 1

(2x+3)(x+4)-(2 -3x)(x-7)=(2x²+3x+8x+12)-(2x-3x²-14+21x)

                                     = 2x²+3x+8x+12-2x+3x²+14-21x

                                     = 5x²-12x+26

Answer 2

\((2x+3)(x+4)-(2-3x)(x-7)\)

\(=2x^2+8x+3x+12-(2x-14-3x^2+21x)\)

\(=2x^2+11x+12-2x+14+3x^2-21x \)

\(=5x^2-12x+26\)

Answer 3

Ta có: \(\left(2x+3\right)\left(x+4\right)-\left(2-3x\right)\left(x-7\right)\)

\(=2x^2+8x+3x+12-\left(2x-14-3x^2+21x\right)\)

\(=2x^2+11x+12+3x^2-23x+14\)

\(=5x^2-12x+26\)