# Math Vocabulary 8.2 Unit rate and problem solving

## 20 terms

### rational number

a number that can be written as a fraction in the form a/b; is an integer b/o

### expression

the part of a number sentence that combines numbers and operations, but doesn't have an equal sign.

### equation

a mathematical statement that two expressions are equal

### area

the number of square units needed to cover a flat surface.

### perimeter

distances around a closed figure.

### congruent

Figures or shapes that have the same size and shape; equal

### isosceles triangle

a triangle with two equal sides

### scalene triangle

a triangle with no two sides of equal length

### composite figure

A figure made of circles, rectangles, squares and other two-dimensional figures.

### unit rate

comparison of a quanity to 1

### ratio

a comparison of two quantities.

### proportion

A statement where two fractions/ratios are equal

### decimal

a proper fraction whose denominator is a power of 10

### fraction

a comparison of parts to a whole

### percent

a ratio that compares a number to 100.

### lateral surface area

The sum of all the areas of the faces of a 3D solid except the bases

### total surface area

The sum of all the areas of the faces of a 3D solid

### B

the area of the base of a solid figure

### P

the perimeter of the base of a solid figure

### polygon

a 2 dimensional closed figure having three or more sides