Bunuel
If the vertices of a triangle have coordinates \((x, 1)\), \((5, 1)\), and \((5, y)\) where \(x \lt 5\) and \(y \gt 1\), what is the area of the triangle?
(1) \(x = y\)
(2) Angle at the vertex \((x, 1)\) is equal to angle at the vertex \((5, y)\)
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Forget about x-y plane as of now. Just draw any triangle with coordinates of vertices as (x, 1) (5, 1) and (5, y)
Now considering we know nothing about the triangle type but we know \(x \lt 5\) and \(y \gt 1\), we assume that we will use Hero's Formula (google if you do not know). We must know all the sides of the triangle to use Hero's formula.
Statement 1
x=y so the coordinates become (x, 1) (5, 1) and (5, x) or (y, 1) (5, 1) and (5, y). Still, we cannot calculate distance between coordinates ie length of each side. Clearly insufficient.
Statement 2 angle at the vertex (x,1)=angle at vertex (5,y)
=> (x-5)^2+(1-1)^2=(5-5)^2+(y-1)^2
or (x-5)^2=(y-1)^2
or (x+y-6) (x-y-4)=0 still we cannot find x and y so insufficeinet
Combining Statement 1 and 2
(2x-6)(-4)=0
2x=6
x=3 or x=y=3.
Calculate the length of three sides and apply the hero's formulae
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