Respuesta :

15x + 6x = 21x
just add the numbers, but Dont forget to put back the "x"
Answer: 21x

Combine like terms. Treat the terms just like regular numbers: 15 and 6. Then add x after your answer.

Ex. 56x + 7x = 63x
      44y - 7y =  37y
     2x + 6y - 8x + y = -6x + 7y

RELAXING NOICE
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