The coordinates of a triangle are the position of the endpoints of the triangle
The coordinates of the third vertex is (2a, 0)
The coordinates of the triangle are:
[tex]\mathbf{A = (0,a)}[/tex]
[tex]\mathbf{B = (0,0)}[/tex]
Because the longer leg is on the x-axis, the y-coordinate will be 0.
So, we have:
[tex]\mathbf{C = (x,0)}[/tex]
Calculate distance AB
[tex]\mathbf{AB = \sqrt{(0 - 0)^2 + (0 - a)^2}}[/tex]
[tex]\mathbf{AB = a}[/tex]
Calculate distance BC
[tex]\mathbf{BC = \sqrt{(0 - x)^2 + (0 - 0)^2}}[/tex]
[tex]\mathbf{BC = x}[/tex]
The longer leg is twice the shorter leg.
So:
[tex]\mathbf{BC = 2BA}[/tex]
Substitute values for BC and BA
[tex]\mathbf{x = 2a}[/tex]
Hence, the coordinates of the third vertex is (2a, 0)
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