Work out the point at which the line y = x^2 + 4x + 4 hits the y-axis and the x value of its turning point.

To work out the point at which the line hits the y axis, we need to know where x = 0. In order to do this, we need to set x = 0, and so we are left with x = 4.
To find the turning point, we need to differentiate the equation. We need to find the derivative of y with respects to the derivative to x. To do this, we remove the x power and -1 times the multiple of x, multiplying the value by its original power i.e. x would go to 1 and x^2 would go to 2x. In this case, we would get dy/dx = 2x + 4, and since we know that the turnig point is the point on a graph where the curve's gradient is 0, we set dy/dx = 0. Solving and rearranging for x, we get 2x = 4, and x = -2.

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Answered by Ethan C. Maths tutor

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