Been stuck on this all day!! Helppp

Step-by-step explanation:

You have to use the arithmetic sequence

f(n)=f(n-1)+d

You can plug in (40,10) and (50,20)

(10)=f(1)+39d

(20)=f(1)+19d

subtract

-10=20d divide

d=-1/2

plug into one of the equations above

(10)=f(1)+39(-1/2)

10=f(1)-39/2

59/2=f(1)

f(1)=29.5

plug into formula

f(n)=29.5-1/2(n-1)

f(n)= -1/2n +30 final equation (Plug in the table values into "n") to solve

if it was like that wouldnt it go from 10 to 20 to 30 to 40 ect.

Step-by-step explanation:

congruent segments

step-by-step explanation: