2x + 3y = 8 and 3x + 2y = 7 find x and y

These are simultaneous equations. To solve them, we need to do something to these equations to that either the coefficents of x or y are the same. So multiply each equation by a suitable number,  a good choice is to multiply Equation 1 by 3, and multiply Equation 2 by 2, which means in both of the equations the coefficient is 6. Next we subtract the second equation from the first, because we want to eliminate the "x" values in each equation leaving us only with y. Then we solve this new equation for y. Next we substitute y = 2 into either Equation 1 or Equation 2 above and solve for x

3 * (Eqn 1) --->    3* (2x + 3y = 8)--->    6x + 9y = 24
2 * (Eqn 2) --->    2 * (3x + 2y = 7)--->    6x + 4y = 14

(6x + 9y = 24  -(6x + 4y = 14) --->5y = 10       
                   

   y = 10/5 = 2

2x + 3(2) = 8
 2x + 6 = 8       

 2x = 2     

  x = 1

Answered by Tara K. Maths tutor

13943 Views

See similar Maths 13 Plus tutors

Related Maths 13 Plus answers

All answers ▸

Simplify 3x+5y+5x-2y


How is our blood sugar regulated?


Factorise the following a) 8x + 6y b) 7xy + 3xzy c)5xyz - 20x^2y^2z


Given the following system of linear equations x - 3y = 5 AND 2x + y = 3 how do I find x and y?


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