Find a missing coordinate when the slope is given

Answer Key - Grade 9 Math Worksheet

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

1. 1.

   The slope is -2. Kira's line has slope -2 and passes through (4, 9). Another point on the line is (8, y). What is y?

   1
2. 2.

   The slope is -3. Noah's line has slope -3 and passes through (1, 7). Another point on the line is (5, y). What is y?

   -5
3. 3.

   The slope is 2. Ari's line has slope 2 and passes through (1, 5). Another point on the line is (x, 19). What is x?

   8
4. 4.

   The slope is -3. Luz's line has slope -3 and passes through (2, 10). Another point on the line is (x, -8). What is x?

   8
5. 5.

   The slope is 1/2. Tala's line has slope 1/2 and passes through (2, 4). Another point on the line is (x, 7). What is x?

   8
6. 6.

   The slope is 4. Jun's line has slope 4 and passes through (3, -2). Another point on the line is (x, 22). What is x?

   9
7. 7.

   The slope is 5. Pia's line has slope 5 and passes through (1, 2). Another point on the line is (x, 27). What is x?

   6
8. 8.

   The slope is 2. Slope = change in y ÷ change in x. Milo's line has slope 2 and passes through (2, 3) and (8, y). Which equation can be solved to find y?

   • (y − 3) ÷ (8 − 2) = 2
   • (y − 3) ÷ (2 − 8) = 2
   • (8 − 2) ÷ (y − 3) = 2
   • (y + 3) ÷ (8 + 2) = 2
9. 9.

   The slope is 4. Slope = change in y ÷ change in x. Zee's line has slope 4 and passes through (1, 3) and (4, y). Which equation can be solved to find y?

   • (y + 3) ÷ (4 + 1) = 4
   • (y − 3) ÷ (4 − 1) = 4
   • (4 − 1) ÷ (y − 3) = 4
   • (y − 3) ÷ (1 − 4) = 4
10. 10.

    The slope is 5. Slope = change in y ÷ change in x. Kira's line has slope 5 and passes through (4, 2) and (7, y). Which equation can be solved to find y?

    • (7 − 4) ÷ (y − 2) = 5
    • (y − 2) ÷ (7 − 4) = 5
    • (y + 2) ÷ (7 + 4) = 5
    • (y − 2) ÷ (4 − 7) = 5