It is known that the sum of the two right sides of a right triangle is 5 cm and the hypotenuse is 2 cm, then the area of the right triangle is 2 cm____ .
Let two right angle sides be a and B, then
(1) A + B = radical 5
(2)a^2+b^2=2^2
Square 1 to get
a^2+b^2+2ab=5
Subtract 2 to get
2ab=1
So the area of the triangle is = AB / 2 = 1 / 4
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