Change between Ax + By = C and y = mx + b, and read the slope and intercepts

Answer Key - Grade 9 Math Worksheet

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

1. 1.

   The line is 2x + 4y = 12. On a worksheet, Kira meets 2x + 4y = 12. What rule in y = mx + b form gives the same line?

   y = -x/2 + 3
2. 2.

   The line is 5x + 2y = 10. In a puzzle book, Zee meets 5x + 2y = 10. What rule in y = mx + b form gives the same line?

   y = -5x/2 + 5
3. 3.

   The line is 4x + 3y = 18. In the warm-up, Milo meets 4x + 3y = 18. What rule in y = mx + b form gives the same line?

   y = -4x/3 + 6
4. 4.

   The line is 6x + 4y = 20. On a poster, Bo meets 6x + 4y = 20. What rule in y = mx + b form gives the same line?

   y = -3x/2 + 5
5. 5.

   Multiply by 3 to clear the fraction. In math club, Pia's rule is y = 2x/3 + 4. What is the same line in the form Ax + By = C, with whole numbers and A positive?

   2x − 3y = -12
6. 6.

   Multiply by 4 to clear the fraction. On a worksheet, Jun's rule is y = 3x/4 − 2. What is the same line in the form Ax + By = C, with whole numbers and A positive?

   3x − 4y = 8
7. 7.

   Multiply by 2 to clear the fraction. In a puzzle book, Tala's rule is y = 5x/2 + 3. What is the same line in the form Ax + By = C, with whole numbers and A positive?

   5x − 2y = -6
8. 8.

   Multiply by 3 to clear the fraction. In the warm-up, Luz's rule is y = x/3 − 5. What is the same line in the form Ax + By = C, with whole numbers and A positive?

   x − 3y = 15

9. Read this first

   Input–output table

   x	y
   0	5
   4	-1

   Solve for y to read the slope.

10. 9.

    Ari sees the line 6x + 4y = 20 in math club. What is its slope?

    -3/2
11. 10.

    Esme sees the line 10x + 4y = 12 in math club. What is its slope?

    -5/2