# What did I do Wrong ?

#### Joe91090

What did I do Wrong ??

1. The problem statement, all variables and given/known data

A car travels 2.14km in the x direction then turns left 71.6 degrees to the original direction and travels an additional distance of 2.58km. calculate the x component of the cars net displacement.

2. Relevant equations

law of cosines

3. The attempt at a solution

plugged knowns into law of cosines equations got 2.78. what did I do wrong ??

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#### gabbagabbahey

Homework Helper
Gold Member
Re: What did I do Wrong ??

Draw a picture, you should have a right triangle. There is no need for the law of cosines.

#### Joe91090

Re: What did I do Wrong ??

Ive drawn several pictures does it just look like a right triangle ?

#### gabbagabbahey

Homework Helper
Gold Member
Re: What did I do Wrong ??

Draw a line downwards from the final position to the x-axis....now do you see the right triangle?

#### Joe91090

Re: What did I do Wrong ??

is your first movemment to the east ?

#### gabbagabbahey

Homework Helper
Gold Member
Re: What did I do Wrong ??

Yes. Isn't yours?

#### Joe91090

Re: What did I do Wrong ??

yes then your 71.6 degrees left so does yours look acute or obtuse ?

#### Joe91090

Re: What did I do Wrong ??

well if your saying its a right angle it must be acute. im still not sure its a right angle

#### gabbagabbahey

Homework Helper
Gold Member
Last edited by a moderator:

#### Joe91090

Re: What did I do Wrong ??

so the answer would be the displacement from (0,0) to the tip of the other vector ?

#### gabbagabbahey

Homework Helper
Gold Member
Last edited by a moderator:

"What did I do Wrong ?"

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