Solve the following simultaenous equations

6a + 3b = 7 (1) 4a + 4b = 12 (2) We need to eliminate one of the variables in our simultaneous equations in order to be able to find a numerical value. As the same signs are used in both equations (i.e. addition), this could be achieved by subtracting one equation from the other, once one of the variables are equated (thus removing this variable). For example: (1) x 4 gives 24a + 12b = 28 (2) x 3 gives 12a + 12b = 36 Thus the b variable is equal in both equations and if we now subtract (2) from (1) we have an equation in a: 12a = -8 and solving gives a = -2/3. Substitute a back into our original (1): (6 x -2/3) + 3b = 7 3b - 4 = 7 b = 11/3 Check in original (2): (4 x -2/3) + (4 x 11/3) = -8/3 + 44/3 = 12 (as this is equal to (2) the values for a and b are correct)

Answered by Millie J. Maths tutor

2797 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

How do you measure the gradient of a straight line joining two points?


Show that ((sqrt(18)+sqrt(2))^2)/(sqrt(8)-2) can be written in the form a(b + 2) where a and b are integers.


how do you solve these simultaneous equations?


Solve the simultaneous equations y = 5x^2 + 4x - 19 and y = 4x + 1


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 2013–2024

Terms & Conditions|Privacy Policy
Cookie Preferences