Question

can anyone tell me the answer of this two question
1.if a=25cm,b=13cm and c=20cm,what is the value of (s-b)?
2.name the mathematician who developed coordinate geometry?

Answer 1

1)s=a+b+c/2=58/2=29cm
2)Rene Descartes

Answer 2

S=(a+b+c)/2 =(25+13+20)/2 =58/2 =29 S-b=29-13 =16