Respuesta :

141 = (13x + 4) + (10x - 1)
141 = 23x + 3  <--- Combine like terms
141 = 23x -3
+3            +3    <--- Simplify by adding 3 to each side
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138 = 23x
/23    /23      <--- Simplify by dividing each side by 23
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x = 6