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# A-level Maths Indices help! watch

1. Find the value of x such that:
27^x = 81

The answer is 4/3 but i really don't get it, also it's non-calculator
If anyone can help it would be very appreciated.
Thanks
2. (Original post by GCSE 9)
Find the value of x such that:
27^x = 81

The answer is 4/3 but i really don't get it, also it's non-calculator
If anyone can help it would be very appreciated.
Thanks
1. Express 27 and 81 as powers of the same number, to get the same base on both sides of the eqn.

2. Use the rules of powers to form an exponent

3. Note that means that
3. Spoiler:
Show

3^3X = 3^4 3X=4 so X= 4/3

Don't read the spoiler unless you are truly stuck after the advice given.

1: Get both numbers as the same base with different powers.
2: The powers are equal to each other if they have the same base and there are no other numbers interfering.
3: Then find X.

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