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

4623 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

When do I use the sin rule and when do I use the cosine rule?


Find the roots of the following function: f(x)= 3*(x-1)^2 - 6.


Expand and simplify the following equation 5a(4b - 3) - 2a(6 + b)


Solve (x+2)/3x + (x-2)/2x = 3


We're here to help

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

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences