Final answer:
To find the length QR, we can use the fact that the sum of two sides of a triangle is greater than the third side. The length of QR is greater than 6.5 cm. Among the given options, the only answer greater than 6.5 cm is 17.5 cm.
Step-by-step explanation:
To find the length of QR, we can use the fact that the sum of the lengths of any two sides of a triangle is greater than the length of the third side. In this case, PQ = 5.5 cm and PR = 12.0 cm. So, we have PQ + QR > PR and QR + PR > PQ.
Substituting the given values, we get 5.5 + QR > 12 and QR + 12 > 5.5.
To find the value of QR, we solve the first inequality: 5.5 + QR > 12. Subtracting 5.5 from both sides gives us QR > 6.5.
Therefore, the length of QR is greater than 6.5 cm. Among the given options, the only answer greater than 6.5 cm is D) 17.5 cm.