Question

Answer 1

1)=2x^2+5x+6x+15

=2x^2+11x+15

=2x^2+5x+6x+15

x=-3,-5/2

Answer 2

3)=-10x^2-2x-15x-3

=-10x^2-13x-3

=-(10x^2+13x+3)

=-(10x^2+10x+3x+3)

=-10x(x+1)+3(x+1)

x=-1,3/10

Answer 3

1: (x+3)(2x+5)

=2x^2+5x+6x+15

=2x^2+11x+15

2: (2x-1)(x-1/4)

=2x^2-1/2x-x+1/4

=2x^2-3/2x+1/4

3: (-2x-3)(5x+1)

=-10x^2-2x-15x-3

=-10x^2-17x-3

4: (x-1)(2x^2+3x-2)

=2x^3+3x^2-2x-2x^2-3x+2

=2x^3+x^2-5x+2

5: (2x-4)(3x^2+5x+1)

=6x^3+10x^2+2x-12x^2-20x-4

=6x^3-2x^2-18x-4

6: =6x+8*căn x-9*căn x-12

=6x-căn x-12