Chapter 4
College Algebra with Corequisite Support · 131 exercises
Problem 49
In 1991 , the moose population in a park was measured to be 4,360 . By 1999, the population was measured again to be 5,880 . Assume the population continues to change linearly. (a) Find a formula for the moose population, \(P\) since 1990 . (b) What does your model predict the moose population to be in \(2003 ?\)
4 step solution
Problem 49
For the following exercises, use the descriptions of each pair of lines given below to find the slopes of Line 1 and Line 2 . Is each pair of lines parallel, perpendicular, or neither? Line 1: Passes through (2,3) and (4,-1) Line 2: Passes through (6,3) and (8,5)
3 step solution
Problem 50
In \(2003,\) the owl population in a park was measured to be \(340 .\) By 2007 the population was measured again to be 285 . The population changes linearly. Let the input be years since \(2003 .\) (a) Find a formula for the owl population, \(P\). Let the input be years since \(2003 .\) (b) What does your model predict the owl population to be in \(2012 ?\)
5 step solution
Problem 50
For the following exercises, use the descriptions of each pair of lines given below to find the slopes of Line 1 and Line 2 . Is each pair of lines parallel, perpendicular, or neither? Line 1: Passes through (1,7) and (5,5) Line 2: Passes through (-1,-3) and (1,1)
3 step solution
Problem 51
The Federal Helium Reserve held about 16 billion cubic feet of helium in 2010 and is being depleted by about 2.1 billion cubic feet each year. (a) Give a linear equation for the remaining federal helium reserves, \(R,\) in terms of \(t,\) the number of years since 2010 . (b) In \(2015,\) what will the helium reserves be? (c) If the rate of depletion doesn't change, in what year will the Federal Helium Reserve be depleted?
3 step solution
Problem 51
For the following exercises, use the descriptions of each pair of lines given below to find the slopes of Line 1 and Line 2 . Is each pair of lines parallel, perpendicular, or neither? Line 1: Passes through (2,5) and (5,-1) Line 2: Passes through (-3,7) and (3,-5)
3 step solution
Problem 52
For the following exercises, write an equation for the line described. Write an equation for a line parallel to \(f(x)=-5 x-3\) and passing through the point (2,-12)
5 step solution
Problem 53
You are choosing between two different prepaid cell phone plans. The first plan charges a rate of 26 cents per minute. The second plan charges a monthly fee of $$\$ 19.95$$ plus 11 cents per minute. How many minutes would you have to use in a month in order for the second plan to be preferable?
5 step solution
Problem 53
For the following exercises, write an equation for the line described. Write an equation for a line parallel to \(g(x)=3 x-1\) and passing through the point (4,9) .
4 step solution
Problem 54
You are choosing between two different window washing companies. The first charges $$\$ 5$$ per window. The second charges a base fee of $$\$ 40$$ plus $$\$ 3$$ per window. How many windows would you need to have for the second company to be preferable?
6 step solution
Problem 54
For the following exercises, write an equation for the line described. Write an equation for a line perpendicular to \(h(t)=-2 t+4\) and passing through the point (-4,-1)
4 step solution
Problem 55
When hired at a new job selling jewelry, you are given two pay options: Option A: Base salary of $$\$ 17,000$$ a year with a commission of \(12 \%\) of your sales Option B: Base salary of $$\$ 20,000$$ a year with a commission of \(5 \%\) of your sales How much jewelry would you need to sell for option A to produce a larger income?
3 step solution
Problem 55
For the following exercises, write an equation for the line described. Write an equation for a line perpendicular to \(p(t)=3 t+4\) and passing through the point (3,1)
5 step solution
Problem 56
When hired at a new job selling electronics, you are given two pay options: Option A: Base salary of $$\$ 14,000$$ a year with a commission of \(10 \%\) of your sales Option B: Base salary of $$\$ 19,000$$ a year with a commission of \(4 \%\) of your sales How much electronics would you need to sell for option A to produce a larger income?
4 step solution
Problem 57
When hired at a new job selling electronics, you are given two pay options: Option A: Base salary of $$\$ 20,000$$ a year with a commission of \(12 \%\) of your sales Option B: Base salary of $$\$ 26,000$$ a year with a commission of \(3 \%\) of your sales How much electronics would you need to sell for option \(\mathrm{A}\) to produce a larger income?
5 step solution
Problem 58
When hired at a new job selling electronics, you are given two pay options: Option A: Base salary of $$\$ 10,000$$ a year with a commission of \(9 \%\) of your sales Option B: Base salary of $$\$ 20,000$$ a year with a commission of \(4 \%\) of your sales How much electronics would you need to sell for option \(\mathrm{A}\) to produce a larger income?
5 step solution
Problem 70
For the following exercises, sketch a line with the given features. An \(x\) -intercept of (-4,0) and \(y\) -intercept of (0,-2)
3 step solution
Problem 71
For the following exercises, sketch a line with the given features. An \(x\) -intercept (-2,0) and \(y\) -intercept of (0,4)
4 step solution
Problem 72
For the following exercises, sketch a line with the given features. A \(y\) -intercept of (0,7) and slope \(-\frac{3}{2}\)
5 step solution
Problem 73
For the following exercises, sketch a line with the given features. A \(y\) -intercept of (0,3) and slope \(\frac{2}{5}\)
6 step solution
Problem 74
For the following exercises, sketch a line with the given features. Passing through the points (-6,-2) and (6,-6)
4 step solution
Problem 75
For the following exercises, sketch a line with the given features. Passing through the points (-3,-4) and (3,0)
5 step solution
Problem 76
For the following exercises, sketch the graph of each equation. $$ f(x)=-2 x-1 $$
5 step solution
Problem 77
For the following exercises, sketch the graph of each equation. $$ f(x)=-3 x+2 $$
5 step solution
Problem 78
For the following exercises, sketch the graph of each equation. $$ f(x)=\frac{1}{3} x+2 $$
4 step solution
Problem 79
For the following exercises, sketch the graph of each equation. $$ f(x)=\frac{2}{3} x-3 $$
4 step solution
Problem 80
For the following exercises, sketch the graph of each equation. $$ f(t)=3+2 t $$
6 step solution
Problem 81
For the following exercises, sketch the graph of each equation. $$ p(t)=-2+3 t $$
5 step solution
Problem 82
For the following exercises, sketch the graph of each equation. $$ x=3 $$
3 step solution
Problem 83
For the following exercises, sketch the graph of each equation. $$ x=-2 $$
4 step solution
Problem 84
For the following exercises, sketch the graph of each equation. $$ r(x)=4 $$
4 step solution