Using the sum of the interior angles of a triangle | Maths

Starter quiz

The sum of 241, 68 and 192 is ______.
- '501' ✓
Simplify the following expression $3x+5y-2x+9y+3x+12$ .
- $8x+14y+12$
- $8x-14y+12$
- $4x+14y+12$ ✓
- $4x-14y+12$
- $18xy+12$
A triangle DEF, where DE = 23 cm, DF = 23 cm and angle EDF is 45° is __________ triangle.
- a scalene
- an isosceles ✓
- an equilateral
- a right-angled scalene
- a right-angled isosceles
Solve $29=54-2x$
- $x=12.5$ ✓
- $x=-12.5$
- $x=41.5$
- $x=83$
- $x=25$
Which of these are correct for the size of the angle marked $n$ ?
- $n=28$
- $n=180-(28+131)$ ✓
- $n=131$
- $n=180-28-131$ ✓
Select the statements that best complete the following sentence. By tearing the corners off of a triangle and arranging them together at a point it you have...
- ...shown that the three angles in a triangle sum to 180°. ✓
- ...demonstrated that the three angles in a triangle sum to 180°. ✓
- ...proved that the three angles in a triangle sum to 180°.