grammar - What is the meaning of りゃ in this phrase?

I came across this phrase while reading an interview.

そういう時はなんて答えりゃいいんだ。

I think it means "At a time like that, such a reply/response is good."

But I don't understand the usage of りゃ. I couldn't find any reference as a suffix or conjugation.

Answer

It's a contraction of 答えれば. More generally, eba contracts to ya:

 kotaereba → kotaerya　　（答えれば　→　答えりゃ）   
     okeba →     okya　　　（おけば　→　　おきゃ）  

      ieba →      iya　　　（言えば　→　　　言や）  
  nakereba →  nakerya　　（なければ　→　なけりゃ）

(As you can see, the pattern is easier to see and describe when romanized.)