Hey there hope this helps you out
Answer:
x=4
Step-by-step explanation:
7x - 9 = 19
add 9 to both sides
7x = 28
divide by 7
x = 4
The practical rule would be, times that number, by the result of the first time you multiplied the first number. But, it would all depend by how much your're raising the number by.
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But, once again, this was an example. This would show and illustrate the rule of "raising a power".<span />
First change them all into either fractions or decimals. Decimals are probably easier though. 1/5 = 0.2; 12/25 = 0.48; 4/5 = 0.8
Order: 0.2, 0.35, 0.48, 0.5, 0.8
Then you change the decimals that you converted back into the fraction form
Answer: 1/5, 0.35, 12/25, 0.5, 4/5