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.

EC
Answered by Ethan C. Maths tutor

3002 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

x is inversely proportional to P. When P = 6, x =2. What does x = when P = 4?


Sue has 2 cats. Each cat eats 1 4 of a tin of cat food each day. Sue buys 8 tins of cat food. Has Sue bought enough cat food to feed her 2 cats for 14 days? You must show how you get your answer.


What is a surd? How would you go by simplifying a surd?


The perimeter of a right-angled triangle is 72 cm. The lengths of its sides are in the ratio 3 : 4 : 5 Work out the area of the triangle.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning