5 times marys age is the same as 28 less than 7 times her age. Find her age

14yrs

Step-by-step explanation:

Mary’s age=x

5•x = x•7-28

=> 5x-7x= -28

=> -2x= -28

=> x= -28/-2

=> x= 14

Step-by-step explanation:

Start by observing that ln(1) = 0

So ln 1^4 = 0 as well.

My calculator says that 4 ln(1) + ln (3) - ln1

is ln(3).

I'm not sure it's right.  Is that a bug or is it actually what the answer is? I will accept it is ln3 but I have my doubts -- especially when when there is a zero involved. If you get a different responder to this and something different is said, I would accept that answer.

Very interesting question.