find an equation of the tangent line at the given point P.
y= 3x^2 + 5x -7, P(-2, -5)
step 1 ... find
step 2 ... using , find the value of the slope of the curve at point P, i.e.
step 3 ... using the slope found in step 2 and the coordinates of the given point P, use the point-slope form of a linear equation to find the equation of the tangent line.