Question #82836

1 Answer
Oct 15, 2016

The rate before lunch = 40 miles/ hour

Explanation:

# 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#