Adding and Subtracting Angle Measurements 4.MD.C.7 Grade Practice ... - Free Printable

Let’s solve this step by step.

We are given a straight line AC with point B on it. From point B, there is a ray BD going upward, forming an angle of 65° with segment BC.

Since AC is a straight line, the total angle at point B along the line must be 180°. That means the angle between AB and BD (let’s call it ∠ABD) plus the angle between BD and BC (∠DBC = 65°) must add up to 180°.

So:

∠ABD + ∠DBC = 180°
∠ABD + 65° = 180°

Now subtract 65° from both sides:

∠ABD = 180° - 65°
∠ABD = 115°

That’s our answer.

Final Answer:
115°