Question

find the value of x if 5 raise to power x-3=22

Answer 1

Here is how.

The expression is : 3711

Lets first resolve 711

So 72=49

So 74=.....1 where 1 is the last digit of the number

So 78=.....1 where 1 is the last digit of the number

So 73=.....3 where 3 is the last digit of the number

So 711=73∗78=........1∗3=.............3 where 3 is the last digit of the number

Now on to 3711=3......3 where 3 is the last digit of the exponent

We know the power is odd and its 3. Lets check out the last digit of some of the odd exponents for 3