Which polynomial is in standard form?

Choice D)  23x^9 - 12x^4 + 19

A single variable polynomial is in standard form when the exponents are decreasing as you move from left to right. The exponents 9, 4, 0 go downhill so to speak.

The term 23x^9 is the leading term with 23 as the leading coefficient. The degree of this polynomial is 9 which is the largest exponent. This polynomial is a trinomial as there are 3 terms here.

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.

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