Thinking Mathematically (6th Edition)

Published by Pearson
ISBN 10: 0321867327
ISBN 13: 978-0-32186-732-2

Chapter 7 - Algebra: Graphs, Functions, and Linear Systems - 7.2 Linear Functions and Their Graphs - Exercise Set 7.2 - Page 432: 64

Answer

See below:

Work Step by Step

(a) Consider the given function: $M\left( x \right)=mx+b$ Here, $m$is the slope of the curve made by the given function, $b$is they–intercept, and x is the variable that represents the year after 1980. The coordinates of the initial and final ends of the line for men shown, respectively, by the red voice balloons are $\begin{align} & \left( {{x}_{1}},{{y}_{1}} \right)=\left( 1980,470 \right) \\ & \left( {{x}_{2}},{{y}_{2}} \right)=\left( 2010,710 \right) \end{align}$ Here, the above values are obtained from the given graph. Consider the equation for the slope of the line: $m=\frac{{{y}_{2}}-{{y}_{1}}}{{{x}_{2}}-{{x}_{1}}}$ Substitute the values in the above equation: $\begin{align} & m=\frac{710-470}{2010-1980} \\ & =\frac{240}{30} \\ & =8 \end{align}$ The red-colored curve on the given graph starts from a point having the coordinate$\left( 1980,470 \right)$. The graph has the x-coordinate at the origin as 1980. The y-intercept of the line represents the value of the y-coordinate when the x-coordinate is at the origin. This shows that the y-intercept of the line is 470, which implies$b=470$. Substitute the values in the given function: $M\left( x \right)=8x+470$ Thus, the function that models the number of the bachelor’s degree awarded to men is$M\left( x \right)=8x+470$. (b) The function $M\left( x \right)=8x+470$ that models the number of the bachelor’s degree awarded to men as calculated in part (a). The value of the x is the year after 1980. It shows that for the year 2020, the value of the x is $\begin{align} & x=2020-1980 \\ & =40 \end{align}$ Consider the obtained function from part$\left( \text{a} \right)$: $M\left( x \right)=8x+470$ Substitute x as 40 in the above equation: $\begin{align} & M\left( 40 \right)=8x+470 \\ & =8\left( 40 \right)+470 \\ & =790 \end{align}$ Thus, the number of bachelor’s degree that will be awarded to men in 2020 is 790 thousand.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.