Equation::
value + value = value
80x + 60(50-x) = 74*50
----
80x + 60*50 - 60x = 74*50
----
20x = 14*50
x = 35 lbs (amt. of 80 cent tea to use)
50-x = 15 lbs (amt. of 60 cent tean to use)
Actual distance is 75 miles
1 inch = 15 miles
Multiply 5x15
Gives you 75
The last statement
AD and DC are equal as shown by the small lines through them
DB is perpendicular and at exactly half way of line AC
Angles CBD and ADB are 92° and 88°
92 + 88 = 180
So the false one must be the last one.
For 3x + 5:
5 is the y-intercept and 3(also 3/1) is the rise over run
