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2 years ago

(7i)(-4i) a. -28i b. 28 c. -28 d. -32i

Mathematics

1 answer:

levacccp [35]2 years ago

6 0

Hey!

Explanation:

↓↓↓↓↓↓↓↓↓↓

First, remove parenthesis.

$7i4i$

Secondly, multiple by the numbers.

$7*4=28$

$-28ii$

Third, apply exponents rule.

$-28i^2$

$i^2=-1$

$-28(-1)$

Finally, refine.

$=28\\$

<u><em>Answer⇒⇒⇒⇒28</em></u>

Hope this helps!

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Have a great day!

-Charlie

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