# What is my misstake (math)?

In the figure ABCD (se attached photo) the angles DAB and CDA are right angles. The length of side BC is 3 cm, the length of CD is 4 cm and the length of AD is 2 cm.
And the problem is to compare the side AB to 6 cm and determine which quantity is greater, with Quantity one being AB and Quantity two being 6 cm and...
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In the figure ABCD (se attached photo) the angles DAB and CDA are right angles. The length of side BC is 3 cm, the length of CD is 4 cm and the length of AD is 2 cm.

And the problem is to compare the side AB to 6 cm and determine which quantity is greater, with Quantity one being AB and Quantity two being 6 cm and the choices are

A. Q1 is greater

B. Q2 is greater

C. Q1 = Q2

D. The information is insufficient

I got A. to be the right answer by dividing the figure into a rectangular with the sides AD and DC and a triangle with the sides AD BC and part of AB and then used pythagoras theorem to find the unknown side, sqrt(3^2-2^2) = sqrt(5) and then AB = DC + sqrt(5) = 4 + sqrt(5) and since sqrt(5) > sqrt(4) = 2 so AB = 4 + something greater than 2 and is therefor greater than 6.

But the answer is supposed to be D, information is insufficient. What is my mistake?

And the problem is to compare the side AB to 6 cm and determine which quantity is greater, with Quantity one being AB and Quantity two being 6 cm and the choices are

A. Q1 is greater

B. Q2 is greater

C. Q1 = Q2

D. The information is insufficient

I got A. to be the right answer by dividing the figure into a rectangular with the sides AD and DC and a triangle with the sides AD BC and part of AB and then used pythagoras theorem to find the unknown side, sqrt(3^2-2^2) = sqrt(5) and then AB = DC + sqrt(5) = 4 + sqrt(5) and since sqrt(5) > sqrt(4) = 2 so AB = 4 + something greater than 2 and is therefor greater than 6.

But the answer is supposed to be D, information is insufficient. What is my mistake?

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