91Ó°ÊÓ

Writing a Linear Function. (a) write the linear function \(f\) such that it has the indicated function values and (b) sketch the graph of the function. $$f(-3)=-8, \quad f(1)=2$$

Use the Vertical Line Test to determine whether \(y\) is a function of \(x .\) To print an enlarged copy of the graph, go to MathGraphs.com. \(x^{2}+y^{2}=25\)

Writing a Linear Function. (a) write the linear function \(f\) such that it has the indicated function values and (b) sketch the graph of the function. $$f(-5)=-1, \quad f(5)=-1$$

Evaluating an Arithmetic Combination of Functions In, evaluate the indicated function for \(f(x)=x^{2}+1\) and \(g(x)=x-4\) . $$(f+g)(2)$$

Determining Quadrant(s) for a Point, determine the quadrant(s) in which \((x, y)\) is located so that the condition(s) is (are) satisfied. $$ x<0 \text { and }-y>0 $$

Determine whether each point lies on the graph of the equation. \(x^{2}+y^{2}=20\) (a) \((3,-2) \quad\) (b) \((-4,2)\)

Verifying Inverse Functions In Exercises \(13-16\) verify that \(f\) and \(g\) are inverse functions. $$f(x)=-\frac{7}{2} x-3, \quad g(x)=-\frac{2 x+6}{7}$$

Testing for Functions Represented Algebraically In Exercises \(11-20\) , determine whether the equation represents \(y\) as a function of \(x .\) $$2 x+3 y=4$$

Verifying Inverse Functions In Exercises \(13-16\) verify that \(f\) and \(g\) are inverse functions. $$f(x)=\frac{x-9}{4}, \quad g(x)=4 x+9$$

Determining Quadrant(s) for a Point, determine the quadrant(s) in which \((x, y)\) is located so that the condition(s) is (are) satisfied. $$ x y>0 $$