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If you double a number and then add 12 you get four fifths of the original number. What is the original number?
Let x equal the number. Then:2x + 12 = 4/5x2x - 4/5x = -126/5x = -12x = -12 * 5/6x = -10
Can you solve these math equations?
1. -8 = z + 3z-8 = 4z (combine like terms, 1 + 3 = 4)-2 = z (divide each side by 4)....................................2. 3a + 12 - 6a = -9-3a + 12 = -9 (combine like terms)-3a +12 -12 = -9 - 12 (subtract 12 from both sides)-3a = -21 (combine like terms)-a = -7 (divide each side by 3)a = 7 (multiply each side by -1)......................3. 2m + 8 - 4m = 28-2m +8 = 28 (combine like terms)-2m = 20 (subtract 8 from each side)m = -10 (divide each side by -2)4. 78 = 3c + 12 - c + 478 = 2c + 16 (combine like-terms)62 = 2c (subtract 16 from each side)31 = c (divide each side by 2).................................5. 4(m + 3) = -324m + 12 = -32 (distribute 4 to whatever is in parenthesis)4m = -44 (subtract 12 from each side.)m = -11 ( divide each side by 4 ).......................................................................6. 40 = 5(d - 2)40 = 5d - 10 (distribute 5)50 = 5d (add 10 to each side)10 = d (divide each side by 5)7. -13 (4 + 2a) = 208-52 + (-26a) = 208 (distribute -13)-52 - 26a = 208 (simplify...)..-26a = 260 (add 52 to each side)a = -10 (divide each side by -26)...............................8. -2(x - 9) = -24-2x - (-18) = -24 (distribute)-2x + 18 = -24 (simplify...)..-2x = -42 (subtract 18 from each side)x = 21 (divide each side by -2)..................9. 3.8(d + 7) = 45.63.8d + 26.6 = 45.6 (distribute 3.8).3.8d = 19 (subtract 26'6 from each side)d = 5 (divide each side by 3.8).................10. 2 + 14z = -8 + 9z2 + 14z -9z = -82 + 5z = -85z = -2 - -85z = -10-10/5z=-2.....................11. 22 + 2x = 37 + 6 + x22 + 2x = 43 + x (combine like terms)22 + x = 43 (subtract x from each side)x = 21 (subtract 22 from each side)............................12. -k = 9(k - 10)-k = 9k - 90 (distribute 9)-10k = -90 (subtract 9k from each and both sides)k = 10 (divide each side by -10).......................13. 8(4 - a) = 2a32 - 8a = 2a (distribute the 8 to what is in the parenthesis)32 = 10a (add 8a to both sides)3.2 = a (divide each side by a 10).......................14. Is the solution to 2x = 3x - 12 - 5x a positive or a negative integer? Explain( please don't copy this exactly, it is plagiarism, and you might lose some points for it) The solution to 2x = 2x - 12 - 5x is a negative integer because it is equal to -2.4 and that is a negative number.2x = 2x - 12 - 5x2x = -3x - 12 (combine like terms)5x = -12 (add 2x to each side)x = -2.4 (divide each side by 5)..................15. The sum of two consecutive integers is -45. What are they?(n) + (n-1) = -45 (write an equation) (( n equals number ))2n-1 = -45 (combine liek terms)2n = -44 (add 1 to each side)n = -22 (divide each side by 2)so your numbers are -22 and -23 because -22 - 1 (the n-1 part) is -23. To check, -22 + -23 = -45.........16. The sum of three consecutive integers is -255. What are they?(n) + (n-1) + (n-2) = -255 (write an equation)3n -3 = -255 (combine like terms)3n = -252 (add 3 to each side)n = -84 (divide each side by 3)so your numbers are -84, -85, and -86. You get the last two because of the (n-1) and the (n-2) and -84 - 1 is -85 and -84 - 2 is -86. To check: -84 + -85 + -86 = -255.You're welcome! Hope this helped!Questioner: Thanks so much my tutor explained this so weird but because you explained how you found the answer i get equations a lot better she had like 6 or 7 different steps. i corrected # 10
