Use your knowledge about parentheses and substitution to solve the following: 7. 2(x + 4) + 10 =

8. 3(6x) + 4 =

9. 10(xy) =

10. 5(x + y) =

11. 2(rs) + 4(x)

12. 2(q) + 2(x + t) =

13. 6(7t + 4s) =

14. 9(10x) + 10y =

15. 2x(xy) =

16. r(s)(t) =

17. (r)(s)(t)(x)(y) =

18. (7x + 2Y) =

7. 2(x + 4) + 10 =2x+18

8. 3(6x) + 4 = 18x+4

9. 10(xy) = 10xy

10. 5(x + y) =5x+5y

11. 2(rs) + 4(x) = 2(rs+2x)

12. 2(q) + 2(x + t) = 2(q+x+t)

13. 6(7t + 4s) = 42t+24s

14. 9(10x) + 10y = 90x+10y

15. 2x(xy) =2x^2y

16. r(s)(t) =

17. (r)(s)(t)(x)(y) =

18. (7x + 2Y) =

I didn't know the last ones- sorry-

answer: c.  

step-by-step explanation:

mixtures containing substances that get attracted to magnet can be separated using a magnet. we can separate iron from a mixture of sand and iron, as only iron attracts to the magnet.

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в.тнєє-¢αявσи ѕυgαя

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∂. иα∂ρн

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