| Solution: | `"Here " a=3, b=4, c=5" (Given)"` 
 
 `"We know that,"`
 
 `"Perimeter" = a + b + c`
 
 ` = 3 + 4 + 5`
 
 ` = 12`
 
 ` `
 
 `"Semi-Perimeter" = s = (a + b + c)/2`
 
 ` = 12/2`
 
 ` = 6`
 
 
 `"Here " a=3, b=4, c=5" and semi-Perimeter" = 6`
 
 `"We know that,"`
 
 `"Area" = sqrt(s (s - a) (s - b) (s - c))`
 
 ` = sqrt(6 (6 - 3) (6 - 4) (6 - 5))`
 
 ` = 6`
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