Question

b)(1-2x)(3x+4)
c)(2x+5)(x-3)
d)(x-3)(5a-2)
e)(a+3)(5a-2)
f)(x+y)(2x-y)

Answer 1

b) (1-2x)(3x+4)=1•3x+1•4-2x•3x- 2x•4=3x+4-6x^2-8x=6x^2-5x+4 c)(2x+5)(x-3)=2x•x+2x•(-3x)+5•x+5•3 = 2x^2-6x^2+5x+ 15=-4x^2+5x+15 d)(b-3)(5a-2)=b•5a+b•(-2)-3•5a-3•(-2) =5ab-2b-15a+6 f)(x+y)(2x-y)=x•2x+x•(-y)+ y•2x+y•(-y) =2x^2-xy+2xy-y^2