Respuesta :

Answer:

E. 36

Step-by-step explanation:

You have to do a² + b² = c²

Plug in

15² + b² = 39²

225 + b² = 1521 (subtract 225 on both sides)

√b² = √1296 (square root on both sides)

b = 36

Hope this helps ya!

The length of the EF in the right-angle triangle is 36 units if the length of DF is 15 units the length of DE is 39 units option (E) is correct.

What is a right-angle triangle?

It is a triangle in which one of the angles is 90 degrees and the other two are sharp angles. The sides of a right-angled triangle are known as the hypotenuse, perpendicular, and base.

We have a right angle triangle shown in the picture.

The length of DF = 15 units

The length of DE = 39 units

As we know, Pythagoras' theorem can be defined as the square of the hypotenuse in a right-angled triangle equal to the sum of the squares of the other two sides.

Applying Pythagoras theorem:

DE² = DF² + EF²

Plug the known values:

39² = 15² + EF²

1521 = 225 + EF²

EF² = 1296

EF = √1296

EF = 36 units

Thus, the length of the EF in the right-angle triangle is 36 units if the length of DF is 15 units the length of DE is 39 units option (E) is correct.

Learn more about the right-angle triangle here:

brainly.com/question/3770177

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