Question

Add without using a number line.

$\left(3\right)+\left(-18\right)$

Answer 1

To add two integers of opposite signs, you need to find the difference in their absolute values and put the sign of the one with the greater absolute value.

Here, $\left(3\right)$and $\left(-18\right)$are of opposite signs. So we find differences in their absolute values.

Hence,

$$\begin{gathered} =\left(3\right)+\left(-18\right) \\ =3-18 \\ =-15 \end{gathered}$$ (Rule: Multiplication of sign + and - is - )

Therefore, $\left(3\right)+\left(-18\right)=-15$