AdamTaurus

Here is the graph of it: https://www.desmos.com/calculator/ox7g6zpagq

Notice that it comes down to a point twice, meaning it has 2 relative minimums.

\(3+10x=-17\)

Subtract 3 from both sides.

\(10x=-20\)

Divide both sides by 10.

\(x=-2\)

To prove it, plug back in.

\(3+10(-2)=-17\)

Multiply before you add.

\(3-20=-17\)

Simplify.

\(-17=-17\)

This is true, so x=-2.

No. I know this one. I can't believe you would accuse me of using google to get the answer for a riddle as simple as this!

There are many ways of explaining/thinking about this riddle. It all boils down to the fact that the lawyers's math is incorrect.

They did NOT spend $9 • 3 + $2.

They spent exactly $27 dollars. $25 for the room and $2 for the tip. Remember they got exactly $3, in total back.

Another way to think about the answer to this riddle is to just pretend that the bellhop refunded $3 to the lawyers (rather than giving them $5 and receiving $2 back).

If the lawyers get $3 back and each takes $1. They they spent exactly $27 dollars.

British Police inspects a room where there are no windows, no doors, no tables and is almost empty expect there is just a puddle of water. They found a dead woman who obviously hung herself from the ceiling, but they are not able to figure out how this had happened. 
Sherlock Holmes and John Watson entered the crime scene and easily able to solve the case.
How did the woman die?

Chicago

You are thunder and your brother is lightning. You can see lightning and hear thunder, and thunder always follows lightning.

Haha good job! Answered all of them correctly!!

This is one of the hardest ones I've got.

Take 9 from 6, 10 from 9, 50 from 40 and leave 6.
How?

Alexander is stranded on an island covered in forest.
One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, k i l l i n g the man in the process.
There are cliffs around the island, so he cannot jump off.
How can the Alexander survive the fire? (There are no buckets or any other means to put out the fire)