How do you graph #y - 7 = -3x# by plotting points?

1 Answer
May 29, 2018

Refer to the explanation below.

Explanation:

#y - 7= -3x#

First begin by rearranging the equation to form a linear function.

#y - 7= -3x#

# y = -3x + 7#

Now, looking at the equation you can see that:

  • the gradient is negative due to the #-3#
  • the graph has been shifted up by #7#

Now, find the point of intersection of the graph along the #y#-axis by making #x = 0#.

#y = -3x + 7#

#y = -3(0) + 7#

#y = 0 + 7#

#y = 7 #

Therefore, #(0,7)# is your point of intersection of the graph with the #y#-axis.

Now, find the point of intersection of the graph along the #x#-axis by making #y = 0#.

# y = -3x + 7#

# 0 = -3x + 7#

# 0 - 7 = -3x#

#(-7) / -3 = (-3x)/-3#

# x = 2.33333#

Now sketch the complete graph.

graph{y - 7= -3x [-4.98, 15.01, -1.88, 8.12]}