Let
and
be, respectively, the length and the width of the rectangle.
If the length is 4 inches more than the width, we have

Moreover, the perimeter of a rectangle is given by

And we can substitute
to get

We know that the perimeter is 34 inches:

Which implies

Do 12x-9 + 141 = 180 (add -9 and 4)
12x +132= 180 (Subtract 132 from 180)
12x =48 (Divide 48 by 12)
x=4
The nearest whole number rounds to 6
The nearest tenth rounds to 5.70
The nearest hundredth rounds to 5.70
The rectangle they give you is 12 units tall. This is the result of scaling by a factor of 1.5, ie it is 1.5 times taller than what the answer will be. Let the answer rectangle have a height of h. This means h*1.5 = 12, or 1.5h = 12
Divide both sides by 1.5 to find that h = 8. The answer rectangle's height is 8 units.
The width's will be treated in a similar manner. I picked on the height since it's easier to see that the height lines up with 12 (the width seems to be between 2 and 4, but its not clear if its at the midpoint).
It would be -3. When you are subtracting a negative, that pretty much means you add that number to the first one. A negative along with another negative would equate to a positive. So it would be -6+3.