How do you evaluate 3a - 5b + c + 2b - a for a=2, b=5, c=4?

1 Answer
Jun 18, 2015

#color( red)(= -7#

Explanation:

Solving by substituting the respective values of #a , b , c# into the expression .

# 3a - 5b + c + 2b -a#

Given:
# a=2 , b = 5 and c=4#

Substituting the same:
# 3 . 2 - 5 . 5 + 4 + 2 . 5 -2#

  • Multiplying the terms
    # 6 - 25 + 4 + 10 -2#
  • Performing addition :
    # 6 + 4 + 10 - 25 - 2#
    # =20 - 25 - 2#
  • Performing subtraction
    # 20 - 27#
    #color( red)(= -7#