A curve has the equation y=x^2+4x+4 and a line has the equation y=2x+3. Show the line and curve have only one point of intersection and find its coordinate..

First set the equations equal to each other: x^2+4x+4 = 2x+3.Rearrange for x in form ax^2+bx+c : x^2+2x+1=0Factorise: (x+1)^2=0. Repeated root, hence only one intersection. x=-1. Using y=2x+3, y=1. So coordinate: (-1,1). Check answers by substituting values back into both equations. Note, I have chosen equations that can be easily factorised at every step so a graphical explanation could be easily conveyed.

EF

Related Maths GCSE answers

All answers ▸

Simplify (x + 3)(2x + 5) - (x - 1)


How will you help with my studies?


Expand the following : (2x+3)(x-1)


x^2+2=18, find the value of x.