Big Book Test 7 Section 4 Q 10

Is the answer D because we can’t assume that if we draw a straight line from Q to PR, the angle will bisect equally?

So, here, we can use the triangle’s property, which is that the sum of any two sides is greater than the third side.

  1. PQ + PR > QR => QR < 13
  2. PQ + QR > PR => 5 + QR > 8. Therefore, QR > 3.

By combining these two inequalities, we know that 3 < QR < 13.
So, there are values of QR which are less than 6, equal to 6 or greater than 6.
This results in option D.

Alternatively, we could have used the equal not equal strategy, testing if 6 is a valid side and then 1 another case (let’s say 7).

I am not really sure what we can achieve if the assumed straight line is indeed an angle bisector. It doesn’t guarantee a similar triangle or division of opposite side equally.

Got it! I didn’t realize what the question was testing! I was trying to bisect and use Pythagorean theorem! Thank you for clarifying this

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