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fighting_cax
- Senior | Next Rank: 100 Posts
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- Location: Philippines
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The trick here is to enclose the triangle in a rectangle as you can see in the attachment that I provided. When you enclose the triangle in a rectangle of width 4 and length 7, you get three triangles that you can easily take the area of. Once you find the area of these triangles, you can take the area of the rectangle which is 7 * 8= 28 square units and subtract the total area of these triangles from it to get the area of triangle PQR.
Triangle 1: Base= 3, Height= 4, Area= (4)(3)/2=6
Triangle 2: Base= 4, Height= 3, Area= (4)(3)/2=6
Triangle 3: Base= 7, Height= 1, Area=7/2
Area of triangle PQR: 28-6-6-7/2=25/2 or 12.5 square units.[/img]
