In order to simplify an expression you have to have the same variables, to the same power.
1a) There are no more H's or numbers without a variable.
1b) The variables do not match.
1c) The variable is to a different power so it can't be simplified.
So to simplify you combine your "like terms"
2a,b, and c are correct :)
2d) already simplified
2e) since the variables are the same, just focus on the numbers (x=h since it won't let me use it) answer: 6x
[tex]10x - 4x \\ 10 - 4 = 6 \\ 6x[/tex]
2g) For this one 9 has no variable and no like terms, so it stays by itself, just focus on the a's (x=a) answer: 9+4x
[tex]9 + 7x - 3x \\ 7 - 3 = 4 \\ 9 + 4x[/tex]
2j) answer: 11y^2+5y
[tex]8y + 6y {}^{2} - 3y + 5y {}^{2} \\ 8y - 3y = 5y \\ 6y {}^{2} { + 5y} {}^{2} = 11y {}^{2} \\ 11y {}^{2} + 5y[/tex]
