Last week Sharon loaned a friend $3 from his wallet. This week Sharon loaned the friend another $18. In dollars, what is the change to Sharon's wallet balance?

21 dollars is the answer

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.