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the legs of a right triangle are in the ratio 3:4 and its area is 1014 cm^2. find the length and perimeter
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It is 3:4:5 right-angled triangle.
(If in a right-angled triangle the two legs are in the ratio 3:4, then the hypotenuse is 5 units long.
Everybody knows it).
So, the length of one leg is 3 units, the length of the second leg is 4 units, and the length of the hypotenuse is 5 units.
Then the area of the triangle is half the product of its legs measures, i.e.
=
,
where x is the length of that unit.
From the condition, you know that the area is 1014
.
It gives you an equation
=
.
Hence,
=
= 169 and x = 13 cm.
Now one leg is 3*13 = 39 cm, the other leg is 4*13 = 52 cm, and the hypotenuse is 5*13 = 65 cm.
Thus the perimeter = 39 + 52 + 65 = 156 cm