Is 21 a prime number?

2 answers:

8 0

21 is not a prime number, its a composite number because its divisible by 3 and 7
and prime numbers only have 1 and its self as factors..
Hope it helps :D

AleksandrR [38]3 years ago

3 0

No.
7×3=21
7×1=21
A prime number can only be multiplied by 1 and itself.

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Evaluate. –1.65 + (–3.4)

elena55 [62]

Hey there!

This seems like a algebraic expression

SO,
Remember: negative and negative = positive
positive and positive = positive
positive and negative = negative
negative and positive = negative

In this problem we will be doing negative and negative so that means our answer will be a negative

Firstly, lets line up our decimals to solve this problem (once when you do that , you can solve it easier)

$-1.65 
\\ +
\\ (-3.4)
$

Answer: $-5.05$

Good luck on your assignment and enjoy your day

~ $LoveYourselfFirst:)$