factorise x^2 - 8x -65

Two numbers add/ subtract to make -8Two numbers multiply to make -65. These are 1 and 65 as well as 5 and 13Seeing as 1 and 65 cant add or subtract to make -8 the numbers we'll use are 5 and 13. These also subtract to make -8.Therefore in the form (x=/-a)(x+/-b). Try:(x+13)(x-5) = X2+ 13x -5x-65 -> so this doesnt workHow about we flip the signs within the brackets(x-13)(x+5) =X2-13x +5x -65 = X2-8x-65

KC
Answered by Kavi C. Maths tutor

5055 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Find the coordinates where the curve f(X)= X^2+X-6 touches the x axis using factorisation.


Solve the simultaneous equations 2x+2y=14 and 3x-y=1


Solve the equation x^{2}-2x-15 = 0


The circle c has equation x^2+ y^2 = 1. The line l has gradient 3 and intercepts the y axis at the point (0, 1). c and l intersect at two points. Find the co-ordinates of these points.


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:

© 2026 by IXL Learning