2times 10 to the 4th subtracted to 7 to the 3ed

2 x 10 4th power - 7 3rd power

2 x 10,000 - 343

20,000 - 343

19,657

I think this is the answer to your problem.  Hope this helped!

-TTL

last option

step-by-step explanation:

given that δdef is right and isoceles,

assuming that side df is the hypotenuse means that de an ef are the other 2 sides that intersect at 90° and are of equal length.

because they are of equal length, we can say that they are congruent

because they intersect at 90°, their slopes must be opposite reciprocals.

only the last option satisfies these conditions.