Find the gradients of the lines that pass through the point (1,7) and are tangent to the parabola y = (2−x)(1+3x).

Y=(2-x) (1+3x)
This is vertical. and that should be 4x=1

Where m is the slope of the line and b is the y-intercept of the line, or the y-coordinate of the point at which the line crosses the y-axis. to write an equation in slope-intercept form, given a graph of that equation, pick two points on the line and use them to find the slope. this is the value of m in the equation.