Answer:

Step-by-step explanation:
The applicable rules of exponents are ...

Your ratio simplifies to ...

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Please note that simplifying the constants, -8/10 to -4/5, eliminates half the answer choices. Since exponents are only multiplied when a power is raised to a power, you can pretty much eliminate the second choice as being unreasonable. ((a^b)^c = a^(bc))
The product of 12 and -5 is -5(12) = -60. Note that 12(-5) = -60 also.
Answer:
Step-by-step explanation:
The trick is not to get all caught up in Pythagoras. There is a much simpler way to do it. Find the area of the triangle two different ways. DG and DE are at right angles. That is one way to find area. The other is use the height (DF) and multiply that by the hypotenuse GE.
DG*DE/2 = GE * DF/2 Multiply both sides by 2
DG*DE = GE * DF
DG = 8
DE = 15
GE = 17
8*15 = 17* DF
120 = 17 * DF Divide by 17
120/17 = DF
DF = 7.06