Question

What should be added to sum of -12 and -21 to get 43

fast please​

Answer 1

Answer:

Given:-

What should be added to the sum of - 12 and - 21 to get 43?

To Find:-

The number to added to the sum of - 12 and - 21 to get 43.

Note:-

●》Sum means addition.

●》Here, we should take the number as variable and for finding the variable usually we rearrange the terms from one side to another that time signs are changed. For example - Positive signs becomes negative signs ; negative signs become positive signs

Solution:-

Two numbers = - 12, - 21 ; Their sum is = 43, Other number = ?, Let it be "x"

☆ According to note first point ( addition means ) and the equation is~

▪︎$x + \ \ - 12 + \ \ - 21 = 43$

☆ According to note second point ( rearrangement )~

▪︎$x + \ \ - 12 = 43 + 21$

▪︎$x + \ \ - 12 = 64$

▪︎$x = 64 + 12$

☆ After doing addition~

▪︎$x = 76$

Checking:-

♤ Let's check both side term are equal or not as equation means both side term equal.

• $x + \ \ - 12 + \ \ - 21 = 43 \ \ ?$

♤ Applying the value~

• $76 + \ \ - 12 + \ \ - 21 = 43 \ \ ?$

• $64 + \ \ - 21 = 43 \ \ ?$

♤ After doing calculations~

• $43 = 43 \ \ ?$

♤ Yes!

Hence, Proved that other number = x = 76.

Answer:-

Hence, the other number to be added to the sum of - 12 and - 21 to get 43 = 76.

:)