### Topics

- Graphing Linear Equations
- Xêz
- Slope

- Graphing Linear Equations
- Xêz
- Slope

- Explain how the slope of a graphed line can be computed.
- Graph a line given an equation in either slope-intercept or point-slope form.
- Write an equation in slope-intercept or point-slope form given a graphed line.
- Predict how changing variables in a linear equation will affect the graphed line.

HSF-LE.A.1a

Prove that linear functions grow by equal differences over equal intervals, and that exponential functions grow by equal factors over equal intervals.HSF-IF.C.7a

Graph linear and quadratic functions and show intercepts, maxima, and minima.HSF-IF.C.7

Graph functions expressed symbolically and show key features of the graph, by hand in simple cases and using technology for more complicated cases.^{*}8.F.A.3

Interpret the equation*y = mx + b*as defining a linear function, whose graph is a straight line; give examples of functions that are not linear.*For example, the function A = s*.^{2}giving the area of a square as a function of its side length is not linear because its graph contains the points (1,1), (2,4) and (3,9), which are not on a straight line8.EE.C.8b

Solve systems of two linear equations in two variables algebraically, and estimate solutions by graphing the equations. Solve simple cases by inspection.*For example, 3x + 2y = 5 and 3x + 2y = 6 have no solution because 3x + 2y cannot simultaneously be 5 and 6*.8.EE.C.8a

Understand that solutions to a system of two linear equations in two variables correspond to points of intersection of their graphs, because points of intersection satisfy both equations simultaneously.8.EE.B.6

Use similar triangles to explain why the slope m is the same between any two distinct points on a non-vertical line in the coordinate plane; derive the equation y = mx for a line through the origin and the equation*y*=*mx*+*b*for a line intercepting the vertical axis at*b*.8.EE.B.5

Graph proportional relationships, interpreting the unit rate as the slope of the graph. Compare two different proportional relationships represented in different ways. For example, compare a distance-time graph to a distance-time equation to determine which of two moving objects has greater speed.

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