human
Simplify algebraic expressions to maintain equivalence by collecting like terms involving just two linear variables Which expression should replace the star in the addition pyramid? ![A pyramid showing the expressions 2a, -b and 2a-2b across the base from left to right. Above the 2a and -b is a star. Above the -b and the 2a-2b is written 2a-3b]() \( 4 a-3 b \)
gpt
Thinks you add all the bricks in a row in an addition pyramid.