Answer:
5.5
Step-by-step explanation:
The y-intercept of the line graph shown above is the value of the point where the line cuts the y-axis. The y-intercept of this graph is between 5 and 6. However, we can get an accurate value by calculation. This can be done by generating an equation of the line.
Recall the slope-intercept equation, 
, where m = slope of the line, b = y-intercept.
To generate the equation of the line, first find slope using the points (-2, 7) and (6, 1):
.
Substitute m = ¾ and the coordinates (6, 1) into the slope-intercept equation to find the y-intercept (b):
Therefore, b = y-intercept = 5.5.
To generate the equation of the line, plug in the values of m and b, we would have:
y = ¾x + 5.5
The y-intercept of the line of the graph is 5.5.
252miles
------------ = 31.5 miles per gallon
8 gal
Answer:
m = 1/3
Step-by-step explanation:
Answer:
45 mph
Step-by-step explanation:
This is a really good question to know the answer to. It is tricky and a bit indirect (which means you have to find something else before you can find the speed of the car.)
Let's keep track of what he does in the time allotted.
How far does Joe go in 5 minutes? That's the amount of time he's on the road before she is.
convert 5 minutes into hours. 5 minutes * 1 hour / 60 minutes = 1/12 of an hour
d = r*t
r = 30 km/hour
t = 1/12 hour
d = 30 km/hr * 1/12 hour = 2.5 km
Now she's about to start. She wants to catch him in 10 minutes
d = r*t
r = x mph
t = 10 minutes = 10 minutes * 1 hour * 60 minutes = 1/6 of an hour.
How far does he go in the 10 minute time?
d = 30 * 1/6 = 5 km
What is his total distance
5 km + 2.5 km = 7.5 km
Finally how fast does she need to go to catch him
d = 7.5 km
r = ? This is what you are trying to find
t = 1/6 of an hour
d = r*t
7.5 km = r * (1/6)hour divide by 1/6 hour
7.5 km // 1/6 hour = r
r = 7.5 * 6 = 45 mph
