# 2 xx x + 3 xx ( x + 10) = 230 #
where # x = #the rate before lunch
# 2x = # the distance traveled by the rate for two hours.
where #( x + 10 ) =# the rate after lunch.
#3 ( x + 10 ) =# the distance travel by that rate for three hours.
#230 =# the total distance traveled.
Solve the equation for x will give the rate before lunch
# 2 xx x + 3 ( x +10) = 230# first multiply across the parenthesis using the distributive property. This gives.
#2x + 3x + 30 = 230# Now use the associate property to add the like terms #2x + 3x = 5x# so
#5x + 30 = 230# subtract 30 from both sides gives
#5x + 30 - 30 = 230-30 # This results in
#5x = 200# divide both sides by 5
# (5x)/5 = 200/5# The answer is
#x = 40#