# 3−1×(8−2×3) = 3 ⋅ 3 − 1 ⋅ 8

#### oldtryingtorenew

##### New member
How can this equation be true? i cant understand how they rewrote 3−1×(8−2×3) to be 3 ⋅ 3 − 1 ⋅ 8. Can someone explain?

#### Steven G

##### Elite Member
3−1×(8−2×3)= 3-(8-6) = 3 - 2 =1
3 ⋅ 3 − 1 ⋅ 8 = 9 - 8 = 1
They did say that you can go from 3−1×(8−2×3) to 3 ⋅ 3 − 1 ⋅ 8. They just said that they are equal.

It similar to saying that 5 + 25 = 15*2. Both sides equal 30, but in computing 5+25 you don't get to 15*2!

D

#### Deleted member 4993

##### Guest
How can this equation be true? i cant understand how they rewrote 3−1×(8−2×3) to be 3 ⋅ 3 − 1 ⋅ 8. Can someone explain?
If you evaluate the Left-Hand-Side and the Right-Hand-Side, you find that "those" collapse to same value (what is it?).

Can you post the complete problem (as it was assigned to you) - verbatim?

That will help us understand the genesis of your query.

#### JeffM

##### Elite Member
How can this equation be true? i cant understand how they rewrote 3−1×(8−2×3) to be 3 ⋅ 3 − 1 ⋅ 8. Can someone explain?
Does the acronym PEMDAS mean anything to you?

#### oldtryingtorenew

##### New member
im trying to understand how we solve
19x≡4(mod141)

now this i understand
141 = 7 ⋅ 19 + 8
19 = 8 ⋅ 2 + 3
8 = 2 ⋅ 3 + 2
3 = 1 ⋅ 2 + 1
2 = 2 ⋅ 1 + 0

now we

D

#### Deleted member 4993

##### Guest
im trying to understand how we solve
19x≡4(mod141)

now this i understand
141 = 7 ⋅ 19 + 8
19 = 8 ⋅ 2 + 3
8 = 2 ⋅ 3 + 2
3 = 1 ⋅ 2 + 1
2 = 2 ⋅ 1 + 0

now we ????
You have NOT completed your thoughts...

#### JeffM

##### Elite Member
Please give the original problem completely and exactly. Your two posts seem to have no relationship to each other.

What are you studying?

You are giving us no information to help us figure out how to help you.

#### Steven G

##### Elite Member
Please give the original problem completely and exactly. Your two posts seem to have no relationship to each other.
You're in a nice mood tonight.

#### Otis

##### Elite Member
i cant understand how they rewrote [the equation]
3−1×(8−2×3) = 3 ⋅ 3 − 1 ⋅ 8

Hi. I can't understand why they would switch multiplication signs on one side.

When you respond to posts #3 and #7, will you please include the source of the exercise/example text, as well?

Cheers
[imath]\;[/imath]

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#### Otis

##### Elite Member
don't get to 15*2!
Steven, I can't call that a factorial faux pas this time!

[imath]\;[/imath]