a)8am-4ab
b)m(a-b)-(b-a)
c)49x²-25y²
d)x²-4x-12
e)y²+9,7y-3

a)8am-4ab=4а(2m-b)b)m(a-b)-(b-a)=m(a-b)+(a-b)=(a-b)(m+1)c)49x²-25y²=(7x-5y)(7x+5y)d)x²-4x-12=(x-6)(x+2)D=16+48=64x1=4+8/2=12/2=6x2=4-8/2=-4/2=-2e)y²+9,7y-3=(y-0,3)(y+10)D= 94,09+12=106,09 (10,3²)y1=-9,7+10,3/2=0,6/2=0,3y2=-9,7-10,3/2=-20/2=-10