Question

HEEEELLLLPPPPPPP MEEEEEEEEEEEE

the question is in the image below:

Answer 1

Answer: 10

Step-by-step explanation:

the formula of circle area is π
`r^(2)` but for this question we use (angle/360)π
`r^(2)` because it is not a full circle.

Then,

angle = 144, the length of JK =
`r`

(144/360)π
`r^(2)` = 40π

(2/5)
`r^(2)` = 40

`r^(2)` = 40*5/2

`r^(2)` = 100

`r` = 10

JK = 10