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How many geometry questions are on the ACT math test?

23

How many degrees are in a circle?

360

How many degrees are in a quadrilateral?

360

Are the diagrams drawn to scale or not to scale?

Usually, the diagrams are drawn to scale.

The square root of 2 is approximately equal to ...?

1.4

The square root of 3 is approximately equal to ...?

1.7

If there is no diagram with a problem, the best thing to do is..?

Draw it yourself.

How long does a line extend?

A line extends forever in either direction.

Collinear

When all points are on the same line.

Line Segment

A line with two endpoints

Endpoints

The points that stop a line

How many degrees is the angle of a line?

180

How many degrees are below a line?

Also 180

Supplementary Angles

Angles that add up to 180º

Vertical Angles

Angles opposite from each other and equal to each other

Perpendicular Lines

When two lines meet so that 90º angles are formed

Parallel Lines

When two lines in the same plane are drawn so that they extend into infinity without ever meeting

Triangle

A three-sided figure whose inside angles always add up to 180º

Isosceles Triangle

A triangle with two equal sides and two equal angles

Equilateral Triangle

A triangle with three equal sides and three equal angles.

All three angles of an equilateral triangle are always equal to..?

60º

Right Triangle

One inside angle is equal to 90º

Hypotenuse

The longest side of the right triangle (opposite the 90º angle)

Isosceles Right Triangle

The sides and angles are always in a particular proportion. The angles are 45º, 45º, 90º and the hypotenuse includes a square root of 2

30-60-90 Right Triangle

Always has the same proportion. The hypotenuse is twice as large and the medium side is equal to the short side times the square root of 3

Area of a Triangle

(base x height)/2

When are triangles similar?

When their angles have the same degree measures; the sides are proportional

Third Side Rule

States that it is impossible for the third side of a triangle to be longer than the total of the other two sides

Quadrilateral

A four - sided figure with four angles that add up to 360º

For any circle problem, four things should be known, which are..?

The radius, the diameter, the area, and the circumference.