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44 votes
What is the value of q in the solution to this system of equations?

2m - 5q = 8
4m + 2q = 64

User Dukbur
by
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2 Answers

25 votes
25 votes

Answer:

q = 4

Explanation:

Step 1: Set up the equation

  • The system of equations can be solved algebraically by substitution or elimination.
  • For substitution, solve one of the equations for m and plug it into the other equation in order to solve for q.
  • For elimination, cancel the m terms in order to solve for q.

Step 2: Solve for q

  • Substitution:
  • 2m - 5q = 8
  • 4m + 2q = 64
  1. 4m = 64 - 2q
  2. m =
    (64-2q)/(2)
  3. m = 16 -
    (1)/(2)q
  4. 2(16 -
    (1)/(2)q) - 5q = 8
  5. 32 - q - 5q = 8
  6. -6q = -24
  7. q = 4
  • Elimination:
  • 2m - 5q = 8 (multiply whole equation by -2 in order cancel m terms)
  • 4m + 2q = 64
  • -2(2m - 5q = 8)
  1. -4m + 10q = -16
  2. 4m + 2q = 64
  3. 12q = 48
  4. q = 4
User ImAtWar
by
2.6k points
15 votes
15 votes
16 because you do 4*16=64
q=3 because
User Nict
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