Question

Verify the following and identify the property:
$\left[\right(-51)+(-26\left)\right]+(-13)=(-51)+\left[\right(-26)+(-13\left)\right]$

Answer 1

$\left[\right(-51)+(-26\left)\right]+(-13)=(-51)+\left[\right(-26)+(-13\left)\right]$

$LHS$

$=[-77]+(-13)$

$=-90$

$RHS$

$=(-51)+\left[\right(-26)+(-13\left)\right]$

$=(-51)+[-39]$

$=-90$

thus,

$LHS=RHS$

$\text{This is commutative property over addition}$