Question

can someone please answer the first four for me? Also can someone please explain it to me, because I don't fully understand​

Answer 1

1                           2

$a^{2} +b^{2} =c^{2} \\9^{2} + 13^{2} =c^{2}\\81+169=c^{2} \\250=c^{2} \\125=c$        $a^{2} +b^{2} =c^{2} \\16^{2} +18^{2} =c^{2} \\256+324=c^{2} \\580=c^{2} \\290=c$

3                          4

$a^{2} +b^{2} =c^{2} \\19^{2} +14^{2} =c^{2} \\361+196=c^{2} \\557=c^{2} \\278.5=c$      $a^{2}+ b^{2}=c^{2} \\10^{2} +11^{2}=c^{2} \\100+121=c^{2} \\221=c^{2} \\110.5=c$