8th grade Word problems that need two equations worksheet

Word problems that need two equations

Grade 8 Math Worksheet - Building Confidence

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

1. Read this first

   Use this

   Two tables (x | y). Animals, x + y = 9: 3 | 6; 4 | 5; 5 | 4; 6 | 3. Legs, 2x + 4y = 26: 1 | 6; 3 | 5; 5 | 4; 7 | 3.

2. 1.

   At a farm, Ren counts 9 animals, ducks (x) and horses (y), with 26 legs in all. Which pair (ducks, horses) is in both tables?

3. Use this

   Two tables (x | y). Tents, x + y = 10: 4 | 6; 5 | 5; 6 | 4; 7 | 3. Campers, 2x + 4y = 28: 2 | 6; 4 | 5; 6 | 4; 8 | 3.

4. 2.

   Esme's camp has 10 tents: small ones for 2 campers (x) and big ones for 4 (y), 28 campers in all. Which pair (small tents, big tents) is in both tables?

5. Use this

   Two condition tables (x | y). Number of party tables, x + y = 7: 2 | 5; 3 | 4; 4 | 3; 5 | 2. Seats, 4x + 6y = 34: 1 | 5; 4 | 3; 7 | 1.

6. 3.

   Jun sets up 7 tables for a class party, some with 4 seats (x) and some with 6 (y), 34 seats in all. Which pair (4-seat, 6-seat) is in both condition tables?
7. 4.

   Luz's quiz has 14 questions: x are worth 2 points and y are worth 5 points. Luz could score 43 points in all. Which system fits?

   • x + y = 43 and 2x + 5y = 14
   • 2x + 5y = 14 and 2x + 5y = 43
   • x + y = 14 and 5x + 2y = 43
   • x + y = 14 and 2x + 5y = 43
8. 5.

   Noah's bean plant is 5 cm and grows 3 cm a week; the pea plant is 11 cm and grows 1 cm a week. Which system gives each height y after x weeks?

   • y = 3x + 11 and y = x + 5
   • y = 3x + 5 and y = x + 11
   • y = 5x + 3 and y = 11x + 1
   • y = 8x and y = 12x
9. 6.

   By Pia's fence, the sunny snowbank is 30 cm, losing 4 cm a day; the shady bank is 18 cm, losing 1 cm a day. Which system gives each depth y on day x?

   • y = 4x + 30 and y = x + 18
   • y = 30x - 4 and y = 18x - 1
   • y = -4x + 18 and y = -x + 30
   • y = -4x + 30 and y = -x + 18
10. 7.

    Tala's team made 10 baskets, 2-pointers and 3-pointers, for 24 points. Could it be 6 two-pointers and 4 three-pointers?

    • Yes: it fits both facts.
    • No: it fits neither fact.
    • No: it fits only the number of baskets.
    • No: it fits only the points.
11. 8.

    A field has 8 animals, ducks and horses, with 22 legs. Zee guesses 6 ducks and 2 horses. Does the guess fit the story?

    • No: it fits neither fact.
    • No: it fits only the number of animals.
    • No: it fits only the legs.
    • Yes: it fits both facts.
12. 9.

    Bo's bean plant is 6 cm, growing 3 cm a week; the pea plant is 18 cm, growing 1 cm a week. The gap shrinks 2 cm a week. When are they equal (weeks, cm)?
13. 10.

    Luz: short book at page 10, +25 pages a day; long book at page 40, +10 a day. The gap shrinks 15 pages a day. When do the pages match? Give (days, page).