Question

If $-9+(-10)=x$, then which of the following is(are) true for the value of $x?$

• A. $-1$
• B. Negative
• C. Positive
• D. $-19$
• E. $1$

Answer 1

Answer: (B), (D)

$-19$

Consider, one red chip is equivalent to $-1$.


$\underset{–}{\text{Need to find:}}$ Value of $x,$ such that $-9+(-10)=x$

To get the value of $-9+(-10),$ we need to add $-9$ and $-10$, i.e., we need to add $9$ red chips and $10$ red chips as one red chip is equivaluent to $-1$.


From the above illustration, it is clear that after adding $9$ and $10$ red chips, we get $19$ red chips in-total, which are equivalent to $-19$.

$\therefore -9+(-10)=-19=x$
So, $x=-19,$ which is negative.

$\underset{–}{\text{Note:}}$
The addition of two negative numbers results in a negative number always.