Houghton Mifflin Harcourt Algebra 2, 2015
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Houghton Mifflin Harcourt Algebra 2, 2015 View details
1. Graphing Absolute Value Functions
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Exercise 7 Page 54

The given function is in the form g(x)=a | 1b(x-h)|+k, where (h,k) is the vertex, a is a parameter for vertical stretch/compression, and b is a parameter for horizontal stretch/compression.

Graph:

Domain: All real numbers
Range: y≥ 7

Practice makes perfect

The given function is in the form of g(x)=a | 1b(x-h)|+k, where (h,k) is the vertex, a is a parameter for vertical stretch/compression, and b is a parameter for horizontal stretch/compression. g(x)=4/3 |(x-5)|+7 ⇓ g(x)=4/3 |1/1(x- 5)|+ 7 We see above that a = 43, b = 1, h = 5, and k = 7. Then, the vertex of g(x) is at (5,7), which means that the parent function is translated 5 units right and 7 units up. ( 0, 0) → ( 5, 7) Since a>1, then g(x), in addition of being a translation, is also a vertical stretch of the parent function by a factor of 43. The x-coordinate of each point on the graph of the parent function will be shifted 5 units to the right, and the y-coordinate will be stretched by a factor of 43 and then moved up 7 units. Let's consider the points (-3,3) and (3,3). (-3,3) & → (-3+ 5,4/3|3|+ 7) → (2,11) (3,3) & → ( 3+ 5,4/3|3|+ 7) → (8,11) Now, we will plot the vertex and the above points, and graph g(x). Recall that the graph of an absolute value function has a V-shape!

We see above that there are no restrictions for the values that the x-variable can take. Moreover, we also see that the y-variable takes values that are greater than or equal to 7. We will use this information to write the domain and range of the function. Domain:& all real numbers Range:& y≥ 7