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Write an equation for the line in point-slope and slope-intercept forms.

Passes through (1, 2) and has a slope of 7.

User Waddie
by
5.9k points

2 Answers

11 votes

Point slope is written as y - y1 = m(x -x1)

Where x1 and y1 are the given point and m is the slope:


point slope :

Y-2 = 7(x-1)


slope intercept is written as y = Mx + b where m is the slope and b is the y intercept:


musing the slope you have y = 7x + b

Now replace y and x with the given point to solve for b:

2 = 7(1) = b

2 = 7 + b

Subtract 7 from both sides to get b = -5


now replace b in the equation to get:

Y = 7x-5

User Svarog
by
6.0k points
2 votes

point-slope form: y-y₁=m(x-x₁)

==========

  • y - 2 = 7(x-1)

slope-intercept form: y = mx + b

==========

  • y - 2 = 7(x-1)
  • y - 2 = 7x-7
  • y = 7x - 7 + 2
  • y = 7x -5
User Massimo Cafaro
by
6.0k points