Angles around Points & Lines Flashcards

All 6 cards in this deck

What do angles at a point add up to?

$360^\circ$

What do angles at a point on a straight line add up to?

$180^\circ$

What are vertically opposite angles?

The pair of angles opposite each other where two straight lines cross — they are equal.

True or false? When two straight lines cross, two angles next to each other add up to $180^\circ$.

True. They are angles on a straight line.

True or false? If someone measures all the angles around a point and they total $350^\circ$, at least one measurement must be wrong.

True. Angles at a point add up to $360^\circ$.

What are the steps to find a missing angle at a point, with a reason?

e.g. angles of $90^\circ$, $130^\circ$ and $x$ meet at a point

1. Add the known angles: $90 + 130 = 220$
2. Subtract from $360$: $360 - 220 = 140$, so $x = 140^\circ$
3. Reason: angles at a point add up to $360^\circ$