Pleases someone explain

When you have a negative exponent, you move the base with the negative exponent to the other side of the fraction to make the exponent positive.

For example:

or

or

When a base with an exponent is divided by a base with an exponent, you subtract the exponents together. (But you can only combine the exponents when the bases are the same)

For example:

  (can't combine because they have different bases of y and x)

When you multiply an exponent directly to a base with an exponent, you multiply the exponents together.

For example:

    First multiply the exponents together in the denominator

       Now subtract the exponents together

 (two negative signs cancel each other out and become positive)

to find the perimeter of the rectangle this is the expression:

x-9+x-9+3x-4+3x-4=138

if we simplify it:

8x-26=138

remember, 138 is what it all adds up to

the length is 11.5cm

the width is 57.5cm

the area is 661.25cm^2

the answers might not be correct use at own risk