EXERCICE 5 3ème URGENT 20 POINTS!!!!!

E= (2x-3)²+(x+8)(2x-3)

=4x²-12x +9+2x²-3x+16x-24

=6x²+x-15

2.

E=(2x-3)x(2x-3)+(x+8)

=(2x-3)x(3x+5)

3.

6x²+x-15

=6(3/2)²+3/2-15

=6(9/4)+3/2-15

=54/4+3/2-15

=27/2+3/2-15

=30/2-15

=15-15

=0