A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours it can go 40 km upstream and 55 km downstream. Find the speed of the boat in still water.

A linear equation is an algebraic equation that involves a constant and a first-order term. The equation is written as y=mx+b, where m is the slope and b is the y-intercept.  Here are some examples of linear equations: y = 3 + 2x y = -0.01 + 1.2x y = 25 + 20x 2x + y - 3 = 0  The graph of a linear equation is a straight line. The slope of a line is the amount by which it rises or falls. It is calculated by the formula rise/run.  Here are some steps for solving linear equations: Expand brackets Group like terms together Simplify the equation Remove constants from the variable Check... Show more

A linear equation is an algebraic equation that involves a constant and a first-order term. The equation is written as y=mx+b, where m is the slope and b is the y-intercept. 

Here are some examples of linear equations:
y = 3 + 2x
y = -0.01 + 1.2x
y = 25 + 20x
2x + y - 3 = 0 

The graph of a linear equation is a straight line. The slope of a line is the amount by which it rises or falls. It is calculated by the formula rise/run. 

Here are some steps for solving linear equations:
Expand brackets
Group like terms together
Simplify the equation
Remove constants from the variable
Check the answer 

Linear equations can be used for many real-world applications, such as:
Calculating the outside temperature from the number of times crickets chirp in one minute
Figuring out how fast a projectile is moving
Converting one unit of measure to another
Calculating rates, such as how quickly a chemical reaction is proceeding.

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