He hates him because he's a Montague and because he humiliated him at the Maskerade.
To fleer and scorn at the Capulets. Tybalt is under the impression that Montagues all hate Capulets so much that whatever they do must in some way be insulting.
Tybalt was asking for a fight with Romeo. Since he was married to Juliet and Tybalt was now his cousin, he refused to fight him. Then Mercutio asked to fight Tybalt and in a way kind of tempted him to fighting. Tybalt ended up killing Mercutio because Romeo got in the way when trying to stop the fight between the two. So now Romeo is angry that his friend Mercutio is dead and Tybalt doesn't have a scratch. So, Tybalt and Romeo fight and Romeo kills Tybalt.
because he is married to Juliet and Tybalt is juliets cousin, so Romeo is related to him. So he doesnt want to fight him.
Romeo had to kill someone, in order for the sequence of events to happen properly. Tybalt has been set up as a quarrelsome man who imagines that he has a grudge against Romeo for crashing Capulet's party (Capulet didn't seem to mind) and so will inevitably create a fight, which creates the occasion for Romeo to kill him.
His wife, at the end of Act II.
Romeo tells off Tybalt at the ball in "Romeo and Juliet." He does so in a polite manner, trying to diffuse the tension between Tybalt and himself.
Basically, he says that Tybalt is mistaken and that Romeo will now go his own way. Tybalt is insulting him to get Romeo mad so he will start a fight, but Romeo backs down because he doesn't want trouble with Juliet's cousin.
he sends him a message challenging him to a deul, as romeo humiliated him by turing up to Tybalt's families masquerade ball, so Tybalt feels as if he needs to seek revenge onm Romeo.
Challenging Tybalt was a rash decision by Romeo as it escalated the conflict between their families. Romeo's actions led to tragic consequences, contributing to the downfall of himself and Juliet. It would have been better for Romeo to find a peaceful resolution rather than engaging in a duel.
What Benvolio might be thinking " Tybalt is so much trouble all he wants to do is start fights, that's what he lives for, I can't stand it. I try so hard to just keep peace but all he does is start conflicts he is a constant thorn in my side. If he wasn't so rash the Capulets and Montagues could be at peace."
broke up the fight but didnt dis-arm Tybalt so he stabbed mercutio around romeo
romeo was so happy about getting married to Juliet the love he was feeling could not be taken over by Tybalt's fury.