In the right-angled triangle QPR. PM is an altitude.

Given that QR = 8 cm and MQ = 3.5 cm, calculate the value of PR.

In the given figure, OD = 2 × OB, OC = 2 × OA and CD = 2 × AB then △ AOB ~ △ COD by :

1. AA

2. SS

3. SAS

4. SSS

If $\dfrac{\text{AB}}{\text{DE}} = \dfrac{\text{BC}}{\text{EF}} = \dfrac{\text{AC}}{\text{DF}}$, then :

1. Δ ABC ∼ Δ EDF

2. Δ ABC ∼ Δ DEF

3. Δ ABC ∼ Δ FDE

4. none of these

If Δ ABC ∼ Δ DEF, then

1. $\dfrac{\text{AB}}{\text{EF}} = \dfrac{\text{AC}}{\text{DF}}$

2. $\dfrac{\text{AB}}{\text{DE}} = \dfrac{\text{BC}}{\text{DF}}$

3. $\dfrac{\text{AC}}{\text{DF}} = \dfrac{\text{AB}}{\text{DE}}$

4. $\dfrac{\text{BC}}{\text{EF}} = \dfrac{\text{AC}}{\text{DE}}$