We know in these kind of triangles that have a 90 degrees angle, we can do:
so the first question:
and then:
so , when you want to rationalize , usually you must multiply the irrational factor as 1:
so , now multiply:
in the next question,we know negative numbers in radical don't have any solution so 2 is correct,
so the first question:
and then:
so , when you want to rationalize , usually you must multiply the irrational factor as 1:
so , now multiply:
in the next question,we know negative numbers in radical don't have any solution so 2 is correct,