Give the slope and y-intercept for each of the lines graphed in Exercise 11.1.

Short Answer

Expert verified
  1. Slope = 1, y-intercept = 0
  2. Slope = -1, y-intercept = 3
  3. Slope = 1/5, y-intercept = 6/5
  4. Slope = 9/8, y-intercept = 15/4

Step by step solution

01

Introduction

A line's slope is defined as the ratio of the vertical change in y to the horizontal change in x between any two locations on the line. It denotes the direction of a line's slant as well as its steepness.

02

Give the slope and y-intercept (1, 1) and (5, 5)

Let, A = (1,1) and B = (5,5).

Slope = (y2-y1)/(x2-x1)

=(5-1)/(5-1)

=4/4

=1

Equation of AB bar is:

y-y1= m(x-x1)

y-1 = 1(x-1)

y-1 = x-1

y=x

Therefore, slope = 1, y-intercept = 0.

03

Give the slope and y-intercept (0, 3) and (3, 0).

Let, A = (0,3) and B = (3,0).

Slope = (y2-y1)/(x2-x1)

=(0-3)/(3-0)

=-3/3

= -1

Equation of AB bar is:

y-y1= m(x-x1)

y-3 = -1(x-0)

y-3= -x

y= -x+3

Therefore, slope = -1, y-intercept = 3.

04

Give the slope and y-intercept (-1, 1) and (4, 2).

Let, A = (-1,1) and B = (4,2).

Slope = (y2-y1)/(x2-x1)

=(2-1)/(4-(-1)

=1/5

Equation of AB bar is:

y-y1= m(x-x1)

y-1 = 1/5(x-(-1)

y-1= 1/5x+1/5

y= (x/5)+(1/5)+1

y= (x+1+5)/5

y=(x+6)/5

y=(x/5)+(6/5)

Therefore, slope =1/5, y-intercept = 6/5.

05

Give the slope and y-intercept (-6, -3) and (2, 6).

Let A=(-6,-3), B=(2,6)

Slope=(y2- y1)/(x2 - x1)

=(6-(-3))/2-(-6)

=9/8

Equation of AB bar is:

y-y1 = m(x-x1)

y-(-3) = (9/8)[x-(-6)]

y+3 = (9/8)(x+6)

y = (9/8)x + 54/8 -3

y = (9x+54-24)/8

y = (9x+30)/8

y= (9x/8)+(30/8)

y=(9x/8)+(15/4)

Therefore, slope = 9/8, y-intercept = 15/4.

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Most popular questions from this chapter

Voltage sags and swells. The power quality of a transformer is measured by the quality of the voltage. Two causes of poor power quality are "sags" and "swells." A sag is an unusual dip and a swell is an unusual increase in the voltage level of a transformer. The power quality of transformers built in Turkey was investigated in Electrical Engineering (Vol. 95, 2013). For a sample of 103 transformers built for heavy industry, the mean number of sags per week was 353 and the mean number of swells per week was 184. Assume the standard deviation of the sag distribution is 30 sags per week and the standard deviation of the swell distribution is 25 swells per week.

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