Solve the simultaneous equations 3x + y = 11 and 2x + y = 8.

First identify which unknown has the same coefficient. In this case it is y.Either add or subtract the two equations to eliminate y. In this case we subtract one equation from the other (can be either). 3x + y = 11- 2x + y = 8 x + 0y = 3which is x = 3.The value of x can now be substituted into either equation to find y.3(3) + y = 11 which is 9 + y = 11. Rearranging to find y we must minus 9 from both sides of the equation to get y on its own on one side of the equation.9 + y - 9 = 11 - 9 gives y = 2.We have now solved the simultaneous equations. We can check our answer is correct by substituting the values of x and y into either original equations. For example 3(3) + 2 = 9 + 2 = 11.




NC
Answered by Natasha C. Maths tutor

3324 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

A straight line goes through the point (7, 5) with a slope of 2. What is the equation of the line?


c is a positive integer. Prove that (6c^3 + 30c) / (3c^2 +15) is an even number.


Bob buys a car for £120 after it is reduced by 20% in the sale. What was the original price of the car?


Make y the subject of the formula x=(2y-1)/(4-y)


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