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How many solutions does the system of equations below have?\newline2xyz=132x - y - z = -13\newline3x2yz=203x - 2y - z = -20\newline3x+y+2z=19-3x + y + 2z = 19\newlineChoices:\newline(A)no solution\newline(B)one solution\newline(C)infinitely many solutions

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Q. How many solutions does the system of equations below have?\newline2xyz=132x - y - z = -13\newline3x2yz=203x - 2y - z = -20\newline3x+y+2z=19-3x + y + 2z = 19\newlineChoices:\newline(A)no solution\newline(B)one solution\newline(C)infinitely many solutions
  1. Combine Equations: Combine the first two equations to eliminate zz.(2xyz)(3x2yz)=13(20)(2x - y - z) - (3x - 2y - z) = -13 - (-20)x+y=7-x + y = 7
  2. Add Equations: Now, let's add the first and the third equation to eliminate zz again.(2xyz)+(3x+y+2z)=13+19(2x - y - z) + (-3x + y + 2z) = -13 + 19x+z=6-x + z = 6
  3. Solve for y and z: We have two new equations:\newlinex+y=7-x + y = 7\newlinex+z=6-x + z = 6\newlineLet's solve for y and z in terms of x.\newliney=x+7y = x + 7\newlinez=x+6z = x + 6
  4. Substitute Back: Substitute yy and zz back into one of the original equations, let's use the first one.\newline2x(x+7)(x+6)=132x - (x + 7) - (x + 6) = -13\newline2xx7x6=132x - x - 7 - x - 6 = -13
  5. Simplify Equation: Simplify the equation. 2xxx=13+7+62x - x - x = -13 + 7 + 6 0x=00x = 0
  6. Infinite Solutions: Since 0x=00x = 0 is true for all xx, we have infinitely many solutions.

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