Check the picture below.
keeping in mind that a circle has a total of 360°, if the twin angles of 72° add up to 144°, what remains for the other twin angles is 360° - 144° = 216°, and that 216 is split between both twins for 108 a piece, taking away the 40° next to ∡2, gives us ∡2.
AB = CB Given
D is the midpoint of AC given
AD= CD Definition of midpoint
Angle BAD = Angle BCD base angle theorem
Triangle ABD = Triangle CBD SAS
Be sure to use your symbols for congruent, etc. I couldn't type those in
Suppose f(x)=6x-2 and g(x)= 2x+4
a.
(f+g) (x) = 6x - 2 + 2x + 4
(f+g) (x) = 8x + 2
b.
(f-g) (x) = 6x - 2 -( 2x + 4)
(f-g) (x) = 6x - 2 - 2x - 4
(f-g) (x) = 4x - 6