# AP BIOLOGY

## HEREDITY

### BACKCROSS OR TESTCROSS

 Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which of these lengths CANNOT represent the sides of a triangle?
 A 32, 34, 60 B 28, 30, 58 C 13, 20, 27 D 2, 4, 5
Explanation:

Detailed explanation-1: -SOLUTION: The sum of the lengths of any two sides of a triangle must be greater than the length of the third side. Since, , you can not form a triangle with side lengths 4 ft, 9 ft, 15 ft. SOLUTION: The sum of the lengths of any two sides of a triangle must be greater than the length of the third side.

Detailed explanation-2: -The lengths 4, 5, 10 also cannot make a triangle because 4 + 5 = 9 < 10 . Look at the pictures below: The arcs show that the two sides would never meet to form a triangle. To make a triangle, two sides must add up to be greater than the third side.

Detailed explanation-3: -Sides of Triangle Rule The rule of the sides of a triangle is that the sum of the lengths of any two sides of a triangle is always greater than the length of the third side. This rule is also known as the triangle inequality theorem. This implies that we cannot have a triangle with lengths 3, 4, 9 as 3 + 4 = 7 < 9.

Detailed explanation-4: -Yes, 9, 40, 41 is a Pythagorean Triple and sides of a right triangle. No, 11, 56, 57 do not represent the sides of a right triangle.

There is 1 question to complete.