A student wants to draw an isosceles triangle with integer sides such
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24 Jul 2021, 05:06
(A) is the answer.
1st Possibility : Sum of the 2 equal side are 12.
If the sum of the two equal side of triangle is 12 then it looks like (A, 6, 6) and the value of A is between 1 to 11.
There are 11 Integers exist for the 1st possibility.
2nd Possibility : Sum of the 2 unequal side are 12.
So, integers available for this case :
Possible : (1, 11, 11) , (2, 10, 10) , (3, 9, 9) , (4, 8, 8) , (5, 7, 7) , (5, 5, 7)
Not possible case because the sum of the two smaller digits is less that the larger number, So those are not possible case. {(1, 1, 11) , (2, 2, 10) , (3, 3, 9) , (4, 4, 8)}
There are 6 integers for the 2nd possibility.
17 (11 + 6) isosceles triangles possible with integer sides are possible such that sum of two of the side is 12.
Hence, (A) is the answer.