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

Answer Key - Grade 9 Math Worksheet - Building Confidence

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

1. Read this first

   Use this

   Input–output table (x | y). Read the point from the numbers with x and with y in y − 4 = 3(x − 2).

2. 1.

   Noah's line is y − 4 = 3(x − 2). Which point is on the line?

   • (2, 3)
   • (4, 2)
   • (-2, -4)
   • (2, 4)

3. Use this

   Input–output table (x | y). Read the point from the numbers with x and with y in y + 1 = 2(x − 5).

4. 2.

   Ari's line is y + 1 = 2(x − 5). Which point is on the line?

   • (5, 2)
   • (-5, 1)
   • (5, -1)
   • (-1, 5)

5. Use this

   Input–output table (x | y). Read the point from the numbers with x and with y in y − 6 = 4(x + 3).

6. 3.

   Luz's line is y − 6 = 4(x + 3). Which point is on the line?

   • (-3, 4)
   • (-3, 6)
   • (6, -3)
   • (3, -6)

7. Use this

   Input–output table (x | y). Read the point from the numbers with x and with y in y + 7 = 5(x + 2).

8. 4.

   Tala's line is y + 7 = 5(x + 2). Which point is on the line?

   • (-2, 5)
   • (-2, -7)
   • (-7, -2)
   • (2, 7)
9. 5.

   Here m = 2, x1 = 1 and y1 = 4. Pia's line has slope 2 and passes through (1, 4). Use y − y1 = m(x − x1). What equation fits?

   y − 4 = 2(x − 1)
10. 6.

    Here m = 4, x1 = 3 and y1 = 6. Bo's line has slope 4 and passes through (3, 6). Use y − y1 = m(x − x1). What equation fits?

    y − 6 = 4(x − 3)
11. 7.

    Here m = 5, x1 = 2 and y1 = 1. Milo's line has slope 5 and passes through (2, 1). Use y − y1 = m(x − x1). What equation fits?

    y − 1 = 5(x − 2)
12. 8.

    Zee works on y − 4 = 3(x − 2). Distributing gives y − 4 = 3x − 6. What is b in y = 3x + b?

    -2
13. 9.

    Ren works on y − 1 = 4(x − 3). Distributing gives y − 1 = 4x − 12. What is b in y = 4x + b?

    -11
14. 10.

    Esme works on y − 9 = 5(x − 2). Distributing gives y − 9 = 5x − 10. What is b in y = 5x + b?

    -1