Question

What is an
equation of the line that passes through the points (5, 7) and (-5, -1)?

Answer 1

• y - 7 = 0.8(x - 5) or
• y = 0.8x + 3

Explanation:

Given

• 2 points (5, 7) and (- 5, - 1)

To find

• Equation of the line passing through the given points

Solution

Find the slope of the line using slope equation:

• 
  `m=(y_2-y_1)/(x_2-x_1)`

• 
  `m=(-1-7)/(-5-5)=(-8)/(-10)=0.8`

Use one of the points and the point-slope equation:

• 
  `y-y_1=m(x-x_1)`
• 
  `y-7=0.8(x-5)`

This can be converted to slope-intercept form:

• 
  `y = mx + b`

• 
  `y -7=0.8(x-5)`
• 
  `y -7=0.8x-0.8*5`
• 
  `y -7=0.8x-4`
• 
  `y =0.8x-4+7`
• 
  `y=0.8x+3`