Answer
Let the number of golden lion tamarins living in zoos be $x$.
$x+1050=1500$
Work Step by Step
Let the number of golden lion tamarins living in zoos be $x$.
We know that $1500$ golden lion tamarins live in wild.
Since this is $1050$ more than golden lion tamarins living in zoos.
We get, $x+1050=1500$