# Glossary

# Angles and Transformations

**alternate angles** – two congruent angles on the opposite side of a transversal that border different parallel lines

**angle** – a figure formed from two rays extending from the same point

**bisect** – to divide into two equal parts

**complementary angles** – two angles that add up to 90°

**congruent** – having the same shape and same size

**corresponding angles** – two congruent angles on the same side of a transversal that border different parallel lines

**dilation** – an enlargement or reduction of a figure

**geometry** – a field of math that studies the relationships between lines, shapes, and three-dimensional figures

**opposite angles** – two angles that don’t touch each other and are formed by crossing lines; also called vertical angles

**parallel** – lines that are exactly the same distance apart and would never meet

**perpendicular** – at a right angle; at 90° to something

**ray** – a line extending indefinitely from a single point

**reflection** – a flip of a figure; a movement of a figure across a line, producing a mirror image

**rotation** – turn; the turning of a figure

**supplementary angles** – two angles that add up to 180°

**transformation** – a change in a shape, or a way of mapping the shape onto another space; examples: translation, reflection, rotation

**translation** – slide; to move a figure along a line

**transversal** – a line that divides two parallel lines

**vertical angles** – two angles that don’t touch each other and are formed by crossing lines; also called opposite angles

# Mixtures and Solutions

**concentration** – the amount of material dissolved in a solution

**dilute** – to make a solution less concentrated, for example, by adding liquid

**dissolve** – to cause to spread out and seem to disappear

**evaporate** – to change from liquid to gas; to dry up

**filter** – a tool to separate larger pieces of something from liquid, often made of paper

**gas** – a state of matter that has no fixed shape or volume, for example, air

**liquid** – a state of matter that has no fixed shape but has a definite volume, for example, water

**matter** – all the stuff things are made of

**mixture** – two or more things combined together

**property** – something you can observe; characteristics, such as size, color, or smell

**saturate** – to make a solution so that no more can be dissolved

**screen** – a tool to separate larger pieces from smaller pieces, often made of metal

**solid** – a state of matter that has a definite shape and volume, for example, a rock

**solubility** – the property of substances that can dissolve

**solute** – the solid part of a solution; the stuff that dissolves in liquid

**solution** – a special kind of mixture with two things mixed together evenly or homogeneously

**solvent** – the liquid part of a solution

**volume** – the amount of space something takes up