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## Algebra 1

### Course: Algebra 1>Unit 4

Lesson 6: Modeling with linear equations and inequalities

# Linear equations & graphs: FAQ

## What is a two-variable linear equation?

A two-variable linear equation is an equation with two unknowns (usually represented by x and y) that can be graphed as a straight line on a coordinate plane.

## What is slope?

Slope is a measure of the steepness of a line. We calculate it by dividing the change in y-values by the change in x-values between two points on a line.
Practice with our Slope from graph exercise.
Practice with our Slope in a table exercise.

## What are horizontal and vertical lines?

Horizontal lines are lines that have a slope of 0, meaning they don't go up or down, while vertical lines have an undefined slope, meaning they don't go left or right.

## What are $x$x-intercepts and $y$y-intercepts?

The x-intercept is the point where a graph crosses the x-axis, while the y-intercept is the point where a graph crosses the y-axis.

## What do mean by modeling with linear equations and inequalities?

Modeling with linear equations and inequalities means using those mathematical concepts to represent or explain real-world situations.

## Why do we need to learn about linear equations and graphs?

Linear equations and graphs come up all the time in mathematics, science, engineering, and business. They're one of the foundational skills for understanding algebra and more advanced math courses. Plus, they can be really useful for modeling real-world situations and solving problems.