The length of the base and height of the triangle as described in the task content are; 6cm and 3cm respectively.
It follows from the task content that the Area of the triangle is; 9 cm².
Since, Area = (1/2)b × h. where h = (b-3).
Therefore we have;
9 = (1/2)b × (b-3)
18 = b² -3b
b² -3b -18 = 0.
On this note, by solving quadratically; we have; b = 6 or b = -3.
The base of the triangle is therefore 6 as it cannot be a negative measure.
Consequently, the height, h = (b-3) = 6-3 = 3.
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