Answer:
Car a is moving at 15 miles per hour
Its slope is 15/1
Its equation is y = 15x
Car b is moving at 7.5 miles per hour
Its slope is 7.5
Its equation is y = 7.5x
Car a is moving twice as fast as car b
Step-by-step explanation:
But here's how you solve
Chose 2 points and find the change in y and change in x, then divide in the same order.
Point 1: (1, 15)
Point 2: (2, 30)
Change in y = 15
Change in x = 1
y = miles
x = hours
15 miles/1 hour
You can also do this
Pick a point and just divide it's y by its x. For example:
(4, 60)
60 miles/4 hours
15 miles per hour
Now that we have the slope, we can get the equation for the graph:
y = 15x + 0
or just y = 15x, because there is no y-intercept
Now let's solve for car b:
Chose a point:
(3, 22.5)
Divide its y by its x
22.5/3
7.5
Car b is moving at 7.5 miles per hour
Now that we have the slope, we can get the equation for the graph:
y = 7.5x + 0
or just y = 7.5x, because there is no y-intercept
Compare the speeds
Car a: 15 mph
Car b 7.5 mph
15 > 7.5
So, Car a > Car b
15/7.5 = 2
So Car a moves twice as fast as Car b
