①.8m²n+2mn
=2mn(4m+1)
②.12xyz-9x²y²
=3xy(4z-3xy)
③.2a(y-z)-3b(z-y)
=2a(y-z)+3b(y-z)
=(2a+3b)(y-z)
④.p(a²+b²)-q(a²+b²)
=(a^2+b^2)(p-q)
①.8m²n+2mn
=2mn(4m+1)
②.12xyz-9x²y²
=3xy(4z-3xy)
③.2a(y-z)-3b(z-y)
=2a(y-z)+3b(y-z)
=(2a+3b)(y-z)
④.p(a²+b²)-q(a²+b²)
=(a^2+b^2)(p-q)