y=mx+c is the equation of a straight line where m is the slope.
m = tanθ where θ is the angle made by the line with the x-axis.
When you are given the equation of a straight line,
first rewrite the equation in the form y = mx+c,
find m, then the angle made by the line with the x axis is
given by
"Show how you can calculate the angles between a straight line (right angle) and the x-axis by using the lines arch(?) and a trigonometric connection"
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