Find the angle (in radians and degrees) between the lines. Round your answer to four decimal places for radians and round your answer to one decimal for degree. i. 4x-4y=4 ii. 5x+4y=6

Respuesta :

Answer:

0.0035 radians  

0.2°    

Step-by-step explanation:

If two non perpendicular lines have slopes m₁ and m₂, the angle between the two straight lines is,

                   tan θ [tex]= |\frac{m_{1} - m_{2}}{1 + m_{1}m_{2}} |[/tex]

                   θ = [tex]tan^{-1}|\frac{m_{1} - m_{2}}{1 + m_{1}m_{2}} |[/tex]

where

θ is angle between two straight lines

m₁ is the slope of the first straight line

m₂ is the slope of the second straight line

The first step is to calculate the slopes of the two straight lines.

Generally, the equation of a straight line is given by,

                          y = mx + c                              

where,

m is the slope or gradient

c is the y-intercept

Line 1 is given to be 4x - 4y = 4. Rearranging the equation we have

                                -4y = -4x + 4

                                    y = x - 1                      ........(1)

Comparing line equation (1) with general line equation for line 1, y = m₁x + c₁

                                 m₁ = 1

Line 2 is given to be 5x + 4y = 6. Rearranging the equation, we have

                                 4y = -5x + 6

                                 [tex]y = \frac{-5}{4}x + \frac{6}{4}[/tex]    ........(2)

Comparing line equation (2) with general line equation for line 2, y = m₂x + c₂

                                [tex]m_{2} = \frac{-5}{4}[/tex]

Now that we have both m₁ and m₂, we can substitute the values of m₁ and m₂ to calculate the angle between the two straight lines.    

                                θ = [tex]tan^{-1}|\frac{1 - (-5/4)}{1 + (1)(-5/4)} |[/tex]

                                θ = [tex]tan^{-1}|\frac{1 + 5/4)}{1 - 5/4} |[/tex]

                                θ = [tex]tan^{-1}|\frac{9/4)}{-1/4} |[/tex]

                                θ = [tex]tan^{-1}|-9|[/tex]

                                θ = [tex]tan^{-1}9[/tex]

                                θ = 0.158°

                                θ = 0.2°      (to 1 decimal place for degree)  

Conversion from degrees to radians

Since  1° = π/ 180 radians

          0.2° = 0.2 × π/ 180 radians

                  = 0.00349 radians

                  = 0.0035 radians   (to 4 decimal places for radians)    

The angle between two straight lines is 0.2° in degrees or 0.0035 radians