Question

Subtract using column method : $-3\mathrm{ab}+4\mathrm{bc}-6\mathrm{ca}$from $2\mathrm{ab}+13\mathrm{bc}+6\mathrm{ca}$

Answer 1

Step 1 : Write the subtrahend ( I.e., the algebraic expression to be subtracted)

Below the minuend ( I.e., the expression from which the subtrahend is to be subtracted ) such that the like terms are in the same column.

$$\begin{gathered} 2\mathrm{ab}+13\mathrm{bc}+6\mathrm{ca} \\ -3\mathrm{ab}+4\mathrm{bc}-6\mathrm{ca} \end{gathered}$$

Step 2 : Change the sign of each term of subtrahend .

$$\begin{gathered} 2\mathrm{ab}+13\mathrm{bc}+6\mathrm{ca} \\ -3\mathrm{ab}+4\mathrm{bc}-6\mathrm{ca} \\ +-+ \\ \mathrm{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_} \end{gathered}$$

Step 3 : Add the two algebraic expressions.

$$\begin{gathered} 2\mathrm{ab}+13\mathrm{bc}+6\mathrm{ca} \\ -3\mathrm{ab}+4\mathrm{bc}-6\mathrm{ca} \\ +-+ \\ \mathrm{\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_} \\ 5\mathrm{ab}+9\mathrm{bc}+12\mathrm{ca} \end{gathered}$$

Hence , $5\mathrm{ab}+9\mathrm{bc}+12\mathrm{ca}$ is the difference between the given algebraic expressions