What is the area of Δ STR?

Answer:  The area of the triangle is:  " 30 ft.² " .
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Explanation:
→ A = " 30 ft.² " .
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Area of a triangle, "A" = 1/2 * (base length) * (perpendicular height) ; 

that is: 

" A = (1/2) * b * h " ; 

→ A = (1/2) * (6 ft) * (10 ft) ;  ←  Plug in the given values from the "diagram" ; 
 
        = (3 ft) * (10 ft) ; 
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→ A = " 30 ft.² " .
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