Algebra: Chapter 10-8, p 460
Mixture Problems
Whether they are acid mixes or coffee bean blends or mixed nuts, we treat these problems the same. `x` will stand for the amount of one of the mixes and the (total amount – x) is the amount of the other mix. Convert percentages to decimals (remember D2P?) and use monetary cost per pound as decimals (like 2 dollars and 4 cents is equal to 2.04) and you’ll be fine.
The problems CAN be solved with 2 variables, `x` and `y`, BUT it requires 2 equations and substitution – I think it is just twice the work of developing one equation with just 1 variable. For these problems, the book and I agree on the easiest method!
Here is a great Purplemath link.
Math-8, Chapter 11-1, p 548
The Language of Geometry
- A point: a specific location in space with no size or shape
- A line: A line is a collection of points that extends indefinitely in 2 directions
- A line segment: A line segment is part of a line containing 2 endpoints and all points between the endpoints
- A ray: A ray is a portion of a line that extends from 1 point indefinitely in ONE direction.
- An angle: When 2 rays have a common endpoint, they form an angle
- Vertex: the common endpoint is called the vertex
- Sides: The rays are called the sides of the angle
- Degree: Common unit of measure for angles is the degree
- Acute angles: have measures greater than 0° but less than 90°
- Right angles: have measures of 90°
- Obtuse angles: have measures greater than 90° but less than 180°
- Straight angles: have measure of 180°
- Parallel lines: lines that never intersect, the symbol is ||
- Perpendicular lines: lines that intersect to form a right angle, the symbol is ⊥