Answer:
i think the rate of change is 1/4 which can be reduced to just 4.
Step-by-step explanation:
i hope this helps :))
(btw i love ur profile pic, BAKUGOOOOOOO)
As the exercise says, the triangles are similar. So, we can set up proportions between correspondent sides.
In order to solve for x we can set up the proportion between the horizontal and vertical sides:

Solving this proportion for x implies 
Now you can solve for m and p using the pythagorean theorem, because both triangles are right:

Then, we know that the hypothenuse of the big triangle is m+p, so we have

which implies

STEP 1:
convert meters to centimeters
100 cm= 1 meter
= 100 cm/m * 2.5 m
= 250 cm
STEP 2:
x= length of first shelf
2x+18= length of second shelf
x-12= length of third shelf
x+4= length of fourth shelf
since the whole board has to be used, add lengths of all shelves and set it equal to the whole length of the board (250 cm).
x + (2x+18) + (x-12) + (x+4)= 250 cm
combine like terms
5x + 10= 250
subtract both sides by 10
5x= 240
divide both sides by 5
x= 48
STEP 3:
find length of second shelf
= 2x + 18
= 2(48) + 18
= 114 cm
CHECK:
x + (2x+18) + (x-12) + (x+4)= 250
48 + (2(48)+18) + (48-12) + (48+4)= 250
48 + (96+18) + 36 + 52= 250
48 + 114 + 36 + 52= 250
250= 250
ANSWER: Shelf two is 114 cm.
Hope this helps! :)
3b - 7 < 32
=> 3b < 32 + 7
=> 3b < 39
=> b < 39÷ 3
=> b < 13
Hope it helps !!!