EX 78
A= 4x^2 +4x+1
A=(2x)^2+2*2x*1+1^2
A=(2x+1)^2
B=x^2 -6x +9
B=x^2 - 2*x*3 +3^2
B=(x-3)^2
C=9x^2 -4
C=(3x)^2 -(2)^2
C=(3x-2)(3x+2)
EX79
A=x(x-1) +2x(x-3)
A= x^2-x+4x^2-6x
A=5x^2-5x
A=5x(x-1)
B=(2x+3)(x-4)+(2x+3)(x+1)
B=(2x+3)[(x-4)+(x+1)]
B=(2x+3)(2x-3)
C=(3x-1)(5x+2) -(5x+2)(2-x)
C=(5x+2)[(3x-1)-(2-x)]
C=(5x+2)(4x-3)