Find mdec
a) 90
b) 95
c) 100
d) 120

C) 100

Step-by-step explanation:

line AC intersects line DB,

hence ∠AEB and ∠DEC are opposite angles and thus

∠AEB = ∠DEC

5x-10 = 4x+12   (subtract 4x from both sides)

5x - 4x - 10 = 12

x - 10 = 12    (add 10 to both sides)

x = 12 + 10 = 22 degrees

∠DEC = 4x+12

= 4(22) + 12

= 88 + 12

= 100 degrees

f(x) is going down by 4

step-by-step explanation:

(its either that or its going left by 4)