Per-Algebra: Chapter 8, Lesson 3
Graphing Linear Equations
To find solutions for linear equations, we can choose ANY values you want for either x or y and then solve for the other term. We are trying to find the ordered pairs (x, y), that fit the equation.
For example, y = -2x + 1. We choose x = 0, 1, 2. If x = 0, then y = 1 [the ordered pair (0,1) ]. If x = 1, then y = -1 (1, 1). If x = 2, then y = -3 (2, -3). We can plot these points on a graph as well. LABEL the x and y axes and also label the numbers positive and negative on the x and y scales.
These equations are called LINEAR EQUATIONS because their graphs are STRAIGHT lines.
Algebra: Chapter 6-2
Difference of 2 Squares
For a binomial to be a difference of 2 squares, 2 conditions must be met.
- There must be 2 terms, both must be square (e.g., 4x^2 and 9x^4)
- There must be a minus sign between the 2 terms.
We are going backward in our factoring, a^2 – b^2 = (a + b) * (a – b), so once we have the 2 squares, just plug them in to our formula!