Question

Please help with number 20

Answer 1

6x

2

−3−7x

=6x

2

−7x−3

=6x

2

−9x+2x−3

=3x(2x−3)+1(2x−3)

=(2x−3)(3x+1).

Then, f(x)=0⟹2x−3=0 and 3x+1=0.

Therefore, 2x=3 and 3x−−1.

That is, x=

2

3

, x=

3

−1

.