5а(а+b) - (3a-b)b+2b(b-a) = 5а(a+b) + (3a+b)b -2b(a-b) = (a+b)(5a+3b-2b) = (a+b)(5a+b)
5a(a+b)-(3a-b)b+2b(b-a)= 5a^2+5ab-3ab+b^2+2b^2-2ab=5a^2+3b^2
5а(а+b) - (3a-b)b+2b(b-a) = 5а(a+b) + (3a+b)b -2b(a-b) = (a+b)(5a+3b-2b) = (a+b)(5a+b)
5a(a+b)-(3a-b)b+2b(b-a)= 5a^2+5ab-3ab+b^2+2b^2-2ab=5a^2+3b^2