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Write the point-slope form of a line that has slope −7 and passes through the point (4, 8)

User Lalit Rawat
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1 Answer

26 votes
26 votes

Answer:

y = -7x + 36

Explanation:

Point-slope form: y - y1 = m(x - x1)

  • y1 = y-value of a point on a line
  • m = slope
  • x1 = x-value of a point on a line

Substitue 8 for y1, and 4 for x1, and -7 for m:

y - y1 = m(x - x1)

y - 8 = -7(x - 4)

Solve:

y - 8 = -7(x - 4) <== distribute -7

y - 8 = -7x + 28 <== add 8 to both sides

+ 8 + 8

y = -7x + 36

Therefore, the point-slope of the line is y = -7x + 36

Check your answer using (4, 8):

y = -7x + 36

8 = -7(4) + 36

8 = -28 + 36

8 = 8

This statement is correct

Hope this helps!

Write the point-slope form of a line that has slope −7 and passes through the point-example-1
User Matthaeus
by
2.9k points