Q3. - Algebra 1

Question

Find each sum or difference.

$20+\left(-7\right)$

Step-by-Step Solution

Answer

The value of expression is 13.

Step 1. Apply the concept of addition and subtraction.

Two numbers with similar signs get added and the resulting number carries the similar sign.

Two numbers with opposite signs get subtracted and the resulting number carries the sign of the larger number.

Step 2. Concept of like and unlike signs.

If there is a sign like $+\left(+\right)$ or $-\left(-\right)$ then the resulting sign will be positive and if there is an unlike sign $+\left(-\right)$ or $-\left(+\right)$ then the resulting sign will be negative.

So, the given sum can be written as

$\begin{array}{l}=20+\left(-7\right)\\ =20-7\end{array}$

Step 3. Evaluate the expression.

Now, subtract the numbers to get

$\begin{array}{l}=20-7\\ =13\end{array}$

Therefore the sum is 13.