y = m x + b is a linear equation.
This equation is in the slope - intercept form, where m is the slope and b is y - intercept.
For example: y = 2 x + 5
In this equation: m = 2 ( the slope ) and b = 5 ( the line intercepts y-axis at the point ( 0, 5 ) ).
To find the distance between her home and her latest position:
According to the question, the diagram is,
Consider the right triangle,
AB=120 km
BC=50 km
To find AC:
Using Pythagoras theorem,

Hence, the distance between the new position and her home is 130 km.
Answer:
I think this ans may help you
(3+5.50)5
8.50*5=42.5
Derek spends $42.50 each school week.
The answer is $85.50
57 x 50% or 57 x .5 = 28.50
Add $28.50 to $57 and you get $85.50