please help me if you can if your going to say I'm cheating i don't care cause i know I'm not thanks!!
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Answer:
13.9 sorry if I'm wrong just trying to help.
Step-by-step explanation:
first plug in your numbers
a*2+ b*2= c*2
12*12= 144
7*7=49
144+49= 193
square root of 193: 13.89244399
rounded to nearest tenth is 13.9