Answer:
X is < 8
Step-by-step explanation:
if y is >0 , then obviously X has to be smaller than 8 otherwise X+y won't be equal to 8
Answer:
40 km on the highway
30 km on the city roads
Step-by-step explanation:
Let x = highway
Let y = city road
The time formula: time = distance / speed.
1) Since we do not know the distance travelled on the highway and city roads but we do know the total time taken, we can say x + y = 70. Set the distances x and y and all equated to 2 hours, since we do not know them, nor do we know the time. This is called a system of equations.
x + y = 70
x/80 + y/20 = 2
2) Solve the system of equations using substitution.
x = 70 - y
---------------
70 - y/80 + y/20 = 2
70 + 3y/80 = 2
y = 30
---------------------------------
x + 30 = 70
x = 70 - 30
x = 40
Therefore, the delivery truck travelled 40 km on the highway and 30 km on the city roads.
