Algebraic Expre...

Identify the like terms in 21p − 32 − 7p + 20p.

If l = −1 and m = 2, then the value of 4l² + 9m² + 2lm − 9l² m is ____.

An expression is taken away from 3x² − 4y² +5 xy +20 to obtain −x² − y² +6 xy+20,then the expression is ____.

If x = −2, y =3 and  z = 1, then the value of expression 

x³ + y³ + z³ − 3 xyz is ___.

?x' packets of 6 sweets each are divided equally among 10 children. How many sweets does each child get?

In a school, 8a² + 4a + 9 students were enrolled. 

2a² − 9a + 2 students were boys. How many girls were enrolled?