Nursing Preparation Study Guide

Nursing Preparation Study Guide 3 . $3.99 = 1 . By cross-multiplying and simplifying we get 1 pound of sugar costs $1.33. 3.5.6 Coordinate Plane A coordinate plane is a two-dimensional number line where the vertical line is called the y the horizontal is called the x -axis. These lines are perpendicular and intersect at their zero points. This point is called the origin. The axes divide the plane into four quadrants. The intersection of the different vertical and horizontal lines creates an ordered pair. The ordered pair is labeled as ( x, y ). The first number corresponds to the x -coordinates and the second to the y -coordinate. To graph an ordered pair on the coordinate plane begin by starting at the origin, (0,0). If the x value is negative, move to the left x units, but if x is positive then you move to the right x units. From there, look at the y value on your coordinate plane. Is y positive? Move up. Is y negative? Move down. To identify the coordinates of an ordered pair that has already been plotted begin at the point itself and follow it down the vertical line. Where does that line cross the x -axis? That is the x component of your ordered pair. Go back to the point and this time trace the horizontal line back to the y -axis. This is the y component of your ordered pair. 3.5.7 Linear Equations A linear equation is an equation made up of two expressions set equal to each other. All linear equations will include: • One or two variables (usually x and y ) • No variable in the equation can be raised to a power greater than 1 • The variable cannot be the denominator of a fraction Examples of Linear Equations: = 3 + 2, = 4, = − < 8 Examples of Non-Linear Equations: = 2 8 , = < } , = √ Linear equations describe the relationship between an independent (x) and dependent variable (y). We typically write linear equations in slope-intercept form, better known as = + . The variable represents the slope of the function. The slope tells us the rise over the run or may units we must move up/down and left/right to get from one point on our line to the other. The variable -axis and

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