Answer:

Step-by-step explanation:


thus, the best car is car B,because it can tavel 29 miles with only one gallon,andcar A can only travel 28 miles with one gallon.
Answer:

Step-by-step explanation:
-5+2(10b-2)=31
Expand brackets.
-5+20b-4=31
-9+20b=31
Add 9 on both sides.
20b=40
Divide both sides by 20
b=2
we know that
A relationship between two variables, x, and y, represent a direct variation if it can be expressed in the form y/x=k or y=kx
so
we have
a) for x=1 y=0.50--------> y/x=0.50/1------> 0.50
b) for x=2 y=1--------> y/x=1/2-------> 0.50
c) for x=3 y=1.50--------> y/x=1.50/3-----> 0.50
d) for x=5 y=2.50--------> y/x=2.50/5----> 0.50
the value of k is equal to 0.50
so
<span>the relationship forms a direct variation. </span>
the equation is
y=0.50*x
Verify
for x=1
y=0.50*(1)------> y=0.50-----> is correct
for x=2
y=0.50*(2)------> y=1.00-----> is correct
for x=3
y=0.50*(3)------> y=1.50-----> is correct
for x=5
y=0.50*(5)------> y=2.50-----> is correct