Answer: Choice B

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Explanation:
The two rules we use are


When applying the first rule to the expression your teacher gave you, we can say that:

Then applying the second rule lets us say

Therefore,

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In short, we just multiplied each exponent inside by the outer exponent 1/2.
So that explains why the exponents go from {1/4,16} to {1/8,8} for x and y in that exact order.
In order to answer this question let's suppose,
Joe is x miles from the beginning and y miles from the end. These assumptions are necessary to answer further:
Now,
x=2y
x+y=30
plugging in x=2y in the above equation
2y+y=30
3y=30
y=10
Hence, according to our calculations, Joe has to hike 10 miles further
Answer: 11
Step-by-step explanation:
Set up an equation
Based on the question, we can determine that 4x = 22 + 2x where x in is the number
"Four times a number" -> <u>4x</u>
"was" -> <u>=</u>
"22 greater than" -> <u>22 +</u>
"twice the same number" -> <u>2x</u>
Put the underlined parts together to get <u>4x = 22 + 2x</u>
Solve equation
Rearrange/collect like terms to solve for x by subtracting 2x from both sides
4x = 22 + 2x
2x = 22
Solve for x by dividing each side by 2
2x = 22
x = 11
Final Answer
x = 11