HELP HELP PLEASE!! D:
Determine the missing side length:
Please don't give cap!

Answer:
c = 35
Step-by-step explanation:
[tex]c^{2} = a^{2} + b^{2}[/tex]
[tex]c^{2} = 21^{2} + 28^{2}[/tex]
[tex]c^{2} = 1225[/tex]
[tex]\sqrt{c^{2} } = \sqrt{1225}[/tex]
[tex]c = 35[/tex]