Can you please help me with this question.
Use a model to find (a+b+c)^2
I would draw a square of side a+b+c
the label the adjoining side as a+b+c.
now, draw lines across the square up and horizontally at a, b, and c.
YOu have divided up your square into nine little rectangles (yes three of them are squares).
Now find the area of the big square by adding all the rectangles.
a^2+b^2+c^2 + 2ab+2ac+2bc
see if that is what you got as the sum of the small rectangles.