Question

Find the additive and multipliactive inverse for each number: 3A. 1.25

Answer 1

Do you know what additive and multiplicative inverse means? We can start there...

Answer 2

I know what it means a little bit but not much. We just started this in our Algerba II

Answer 3

Additive inverse is simply the number that when added to the other number equals 0. So \[1.25+? = 0\]

Answer 4

25 + 0 = 0? Is thar right?

Answer 5

That**

Answer 6

First, let me clear something up: "3A. 1.25" So the problem is 3A and the value given is 1.25 right?

Answer 7

Yepp

Answer 8

Ok...so what could you add to 1.25 which would result in a value of 0?

Answer 9

0?

Answer 10

1.25 + 0 = 1.25

That's not it :)

Answer 11

Since 1.25 is positive...you should see that you must add a negative number to make it 0. Therefore, the answer would be -1.25:\[1.25+(-1.25)=0\]That's a true equation.

Answer 12

Right so it would be a -1.25 as a answer?

Answer 13

Yes

Answer 14

Alright so basically just switching a positve to a negative answer.

Answer 15

Maybe...

If you're original number was -1.25...the additive inverse would actually be +1.25

Answer 16

If you're ok with everything above...we can discuss multiplicative inverses

Answer 17

Yeah thats alright so for 3A it would be -1.25?

Answer 18

Yes, that's additive inverse answer.

Answer 19

You still need to do the multiplicative inverse also.

Multiplicative inverse is simply defined as the number that when multiplied times the original number result in an answer of 1. In essence, it's going to be the reciprocal of the original value.
\[(1.25)(\frac{1}{1.25})=1\]So the multiplicative inverse of 1.25 is 1/1.25.

You could also express this (as well as the additive inverse as a fraction which may be what your teacher wants:\[1.25=\frac{5}{4}\]So the additive inverse would be :\[-\frac{5}{4}\] and the multiplicative inverse would be \[\frac{4}{5}\]