Questions | 5 |

Topics | Angles Around Lines & Points, Cylinders, Line Segment, One Variable, Rhombus |

Angles around a line add up to 180°. Angles around a point add up to 360°. When two lines intersect, adjacent angles are **supplementary** (they add up to 180°) and angles across from either other are **vertical** (they're equal).

A cylinder is a solid figure with straight parallel sides and a circular or oval cross section with a radius (r) and a height (h). The **volume** of a cylinder is π r^{2}h and the **surface area** is 2(π r^{2}) + 2π rh.

A line segment is a portion of a line with a measurable length. The **midpoint** of a line segment is the point exactly halfway between the endpoints. The midpoint **bisects** (cuts in half) the line segment.

An equation is two expressions separated by an equal sign. The key to solving equations is to repeatedly do the same thing to both sides of the equation until the variable is isolated on one side of the equal sign and the answer on the other.

A rhombus has four equal-length sides with opposite sides parallel to each other. The perimiter is the sum of the lengths of all sides (a + b + c + d) or, because all sides are the same length, 4 x length of one side (4s).