At what point(s) do lines y = x^2 - 5x - 14 and y = 3x + 2 intersect? Write your answer in surd form

To find the point(s) where these two lines intersect we will first find the x coordinate of the point(s) where they intersect snd use this to find the corresponding y coordinate by substituting the x value into one of the linear equations. To find the x value(s) we can use the fact that y = y, so we can write x2-5x-14 = 3x+2 since x2-5x-14 = y and 3x+2 = y. We can rearrange this to get x2-8x-16=0 which is a quadratic equation, meaning we can use the quadratic formula to find our x value(s).
You should find that there are two x values, x = 4 + 4(sqrt(2)) and x = 4 - 4(sqrt(2)) (sqrt(2) is square root 2!)We can now use these x values to find their corresponding y values simply by substituting them into y = 3x + 2.Doing this we find that the points where the two lines intersect are (4 + 4(sqrt(2)), 14 + 12(sqrt(2))) and (4 - 4(sqrt(2)), 14 - 12(sqrt(2))). To double check your values try substituting your x values into the other linear equation and see if they give you the same answer!

KJ
Answered by Kieran J. Maths tutor

3689 Views

See similar Maths A Level tutors

Related Maths A Level answers

All answers ▸

The line L1 has vector equation,  L1 = (  6, 1 ,-1  ) + λ ( 2, 1, 0). The line L2 passes through the points (2, 3, −1) and (4, −1, 1). i) find vector equation of L2 ii)show L2 and L1 are perpendicular.


integration by parts: x^-2lnx


How to differentiate with respect to x, xsin2x.


Differentiate y=x^3


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences