Answer:
y=(x-1)(x-4) & 100°
Explanation:
Graph
1) there are x-intercepts at 1 and 4so you set those equal to x
ex. x=1 x=4
2) then subtract them over to equal 0 and set it equal to y
ex. y=(x-1)(x-4)
Angle
*IMPORTANT* Straight lines are equal to 180°
∠CBD = 80°
1) So you just subtract ∠CBD from 180°
ex. 180° - 80° = 100°