Please note translations are just movements on a axis, they are not changing the length of a segment at all. In fact, only dilations change the figure. The length of E'F' is going to be the same as the length of EF.
First you need to find the X You know that since its a parallelogram opposite sides are congruent so you would do the following equation
(The work below goes vertical)
2x+3=3x-1
-3x-3I-3x-3
---------------
-x =-4
/-1 /-1
----------------
x= 4
So now that we know x=4 we plug it into the side
4+2=6
Then you multiply is by two since df goes across the whole shape and u get 12
Hope that helps
Use
bodmas
multiply 6 and 3= 18
then add the answer with 23
18+23=455
the answer you get, subtract it from 7
455-7=448
the answer is 448
