Question

Angle DEF is a right triangle. If FE = 12 and DE = 5, find DF.

Answer 1

Answer:

Option D is correct.

side DF = 13 units

Step-by-step explanation:

Using Pythagoras theorem:

$\text{Hypotenuse side}^2=\text{Opposite side}^2+\text{Adjacent side}^2$          ....[1]

In a right angle triangle DEF:

FE = 12 units and DE = 5 units.

Using Pythagoras theorem on DEF we have;

Hypotenuse side = DF

Opposite side = DE and Adjacent side = FE

Substitute these in [1] we have;

$DF^2 = 5^2+12^2 = 25 +144 = 169$

⇒$DF = \sqrt{169} = 13$ units.

Therefore, the side DF = 13 units

Answer 2

c^2=a^2+b^2

c^2 = 12^2 + 5^2

C^2 = 144 +25

C^2 = 169

c=13

DF = 13