Answer:
[tex]b^{2} + 2ab - a^{2}[/tex]
Step-by-step explanation:
We can solve this problem applying the distributive proprierty.
We also have to be careful with the negative signal.
So
[tex]b(a+b) - a(a-b) = ba + b^{2} - (a^{2} - ab) = ba + b^{2} - a^{2} + ab = b^{2} + 2ab - a^{2}[/tex]
Important to note that [tex]ba = ab[/tex]. For example, [tex]2*3 = 3*2[/tex]
