How do I solve this pair of simultaneous equations: 3x+y=7 and 3x-y=5?

Step 1: Eliminate the ‘y’ component from the equations by adding the equations together. This gives the new equation ‘6x=12’

Step 2: Find the value of x by dividing both sides of the equation by 6. This gives us the value of x=2.

Step 3: Use this value of x to find the value of y, by substituting x=2 into one of the two original equations. For example, using the first equation: 6+y=7. By subtracting 6 from both sides of the equation, we find that y=1.

Step 4 (optional but recommended): To check that these values of x and y are correct, substitute both these found values into the original equation that you haven’t already used. Using the second equation, we can verify that 3x-y=5 is correct when x=2 and y=1. We can therefore have full confidence that we have the correct answer!

Answered by Alisha M. Maths tutor

3155 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve, using the quadratic formula, the equation x^2 +2x=35


Express 6x^2+4x-1 in the form a(x+b)^2+c


168 is 4/7 of a number. What is the number?


Solve the simultaneous equations 5x+2y=11 and x-y=-2.


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