Point-slope form: graph a line from it, and write an equation in it

Answer Key - Grade 9 Math Worksheet

Circle the best answer, or write your answer on the line.

1. 1.

   The slope is -2. Noah's line has slope -2 and passes through (3, -1). What equation fits, in point-slope form?

   y + 1 = -2(x − 3)
2. 2.

   The slope is 4. Ari's line has slope 4 and passes through (-2, 5). What equation fits, in point-slope form?

   y − 5 = 4(x + 2)
3. 3.

   The slope is 3. Luz's line has slope 3 and passes through (-4, -3). What equation fits, in point-slope form?

   y + 3 = 3(x + 4)
4. 4.

   The slope is -3. Tala's line has slope -3 and passes through (6, 2). What equation fits, in point-slope form?

   y − 2 = -3(x − 6)
5. 5.

   “The rule is y + 2 = 3(x − 4)” Jun's line is y + 2 = 3(x − 4). What is the rule in y = mx + b form?

   y = 3x − 14
6. 6.

   “The rule is y − 5 = -3(x − 1)” Bo's line is y − 5 = -3(x − 1). What is the rule in y = mx + b form?

   y = -3x + 8
7. 7.

   “The rule is y − 5 = 4(x + 2)” Milo's line is y − 5 = 4(x + 2). What is the rule in y = mx + b form?

   y = 4x + 13
8. 8.

   “The rule is y + 1 = -2(x − 3)” Zee's line is y + 1 = -2(x − 3). What is the rule in y = mx + b form?

   y = -2x + 5

9. Read this first

   Input–output table

   x	y
   -1	2
   3	10

10. 9.

    Esme's line passes through (-1, 2) and (3, 10). Use the first point. What equation fits, in point-slope form?

    y − 2 = 2(x + 1)
11. 10.

    Noah's line passes through (4, 1) and (8, 4). Use the first point. What equation fits, in point-slope form?

    y − 1 = (3/4)(x − 4)