The correct answer is: [C]: " 8.64 mm² " .
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Note:
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Area of a triangle = (½)*(base length)*(height; that is, "perpendicular height");
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or: A = (½) * b * h ;
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Given: "b = 4.8 mm" ;
"h = (¾) * b = (¾)* (4.8 mm) = 3.6 mm ;
→ h = 3.6 mm ;
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→ A = (½) * b * h ;
= (½) * (4.8 mm) * (3.6 mm) ;
→ A = 8.64 mm² ; which is: Answer choice: [C] .
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