ab + ac = a( b + c )
ab - ac + ad = a( b - c + d )
ax + bx - cx + dx = x( a + b - c + d )
1)ab+ac=a(b+c)
2)ab-ac+ad=a(b-c+d)
3)ax+bx-cx+dx=x(a+b-c+d)
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ab + ac = a.(b + c )
ab - ac + ad = a.( b - c + d )
ax + bx - cx + dx = x.( a + b -c + d )