Then the tilt angle of l2 is θ+45 (this even means angle, because the angle is counterclockwise by default, so it is added here).
Because l 1:y=( 1/2)*x+2.
So tanθ= 1/2.
Therefore, the slope of l2 is k = tan (θ+45) = (tan θ+tan 45)/(kloc-0/-tan θ * tan 45) = (1/2+1)/(kloc-0/-65438+).
So the equation of l2 line is y- 1=3(x+2).
That is, y=3x+7.
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