Question

1. combine any like terms in the expression. if there are no like terms, rewrite the expression. $42st^{2}+41st^{2}+28st^{2}+28st^{2}-3st^{2}$

Explanation:

Step1: Identify like terms

All terms have $st^2$, so combine coefficients.

Step2: Sum the coefficients

$42 + 41 + 28 + 28 - 3$

Step3: Calculate the total

$42+41=83$; $83+28=111$; $111+28=139$; $139-3=136$

Step4: Attach the common term

Multiply the total coefficient by $st^2$

Answer:

$136st^2$