51. I checked the comments but I still didn't understand it, sorry :/
54.
(43+45+47+49)=184
They are all odd and they are in consecutive order (one after another)
Answer:
Step-by-step explanation:
2.5cm=25 mm
2.9cm=29 mm
3.1cm=31 mm
They give it in cm because it’s easier to guess how long it will be in real life
Multiply 4 with (2x-5)
8x-20+15=11
add 20 both sides
8x+15=31
subtract 15 both sides
8x=16
divide both sides by the x (8)
x=2
F(x)=3x+18
That is the awnser they I got