ex3
B
[tex](2x + 3)(4x + 6) \\ = 8x {}^{2} + 12x + 12x + 18 \\ = 8x {}^{2} + 24 x + 18[/tex]
c
[tex](5x - 3)(3x - 8) \\ = 15x {}^{2} - 40x - 9x + 24 \\ = 15x {}^{2} - 49x + 24[/tex]
d
[tex] (2x + 3)(5x + 2) + (2x - 4)(x + 1) \\ = 10x {}^{2} + 4x + 15x + 6 + 2x {}^{2} + 2x - 4x - 4 \\ = 12x {}^{2} + 17x + 2[/tex]
ex4
e
[tex]2x {}^{2} + 7x = x(2x + 7)[/tex]
f
[tex](x - 5)(2x - 3) - (x - 5)(x + 12) \\ = (x - 5)(2x - 3 - x - 12) \\ =( x - 5)(x - 15)[/tex]
g
[tex](x - 2) {}^{2} + (x - 2)(2x + 9) \\ = (x - 2)(x - 2 + 2x + 9) \\ = (x - 2)(3x + 7)[/tex]
