Question

Which expression demonstrates the use of the commutative property of addition in the first step of simplifying the expression (–1 + i) + (21 + 5i)?

Answer 1

We have to find the expression which demonstrates the use of the commutative property of addition in the first step of simplifying the given expression (–1 + i) + (21 + 5i).

Commutative property of addition states:

"The sum of two whole numbers remains the same even if the order of whole numbers is changed" or

Mathematically" a+b=b+a".

Consider the given expression

(–1 + i) + (21 + 5i)

= (-1+21)+(i+5i) is the required step which demonstrates the use of the commutative property of addition.

Answer 2

(–1 + i) + (21 + 5i) + 0

–1 + (i + 21) + 5i

(–1 + 21) + (i + 5i)

–(1 – i) + (21 + 5i)

Answer: (–1 + 21) + (i + 5i)

This is an another similar query, maybe you can understand better from this:

Q: Which expression demonstrates the use of the commutative property of addition in the first step of simplifying the expression (–3 + i) + (18 + 5i)?

Ans: -3+i+18+5i ,you'll gather the real numbers and the imaginary together, right?

-3+18 + i+ 5i. You've swapped i and 18, commutative: i+18 = 18+i

The final answer is 15+6i