[tex]a) \ (3-2x)(3x+5) = 9x + 15 -6x^{2}-10x = -6x^{2}-x+15\\\\b) \ (2a-b)(b-3a) = 2ab - 6a^{2}-b^{2}+3ab = - 6a^{2}+5ab-b^{2}\\\\c) \ (5+2n)(3-2m) = 15-10m+6n-4mn\\\\d) \ (z-y)(z+y) = z^{2}-y^{2}[/tex]
