Solve the Simultaneous Equation: 2x + 3y = 15 and 5x + 4y = 13

Primarily, we should attempt to make either the x or y values of either equation be the same value, or the equivalent negative value. This is so we can add or subtract the equations to leave us with one variable. In this case, we should multiply the first equation by 5 to leave us with 10x + 15y = 75, and multiply the second by 2, leaving us with 10x + 8y = 26.Then we should subtract the second equation from the first equation, leaving us with 7y = 49. By dividing both sides by 7, we find our first variable y. Y is therefore equal to 7.
Then if we look at the original question, y can be inserted into either of the equations. If we take the first one, the equation that results is 2x + (3*7) = 15. The three and the seven multiply so 2x + 21 =15. If we subtract 21 from both sides, the equation we are left with is 2x = -6. By dividing both sides by 2, the answer for variable x is -3.Thus the solution to the simultaneous equation is x = -3 and y = 7

Answered by Luke H. Maths tutor

6645 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

How do I find the missing length using trigonometry?


A flight travels at 750kmph for 7 hours and 18 minutes, work out the distance travelled? Then convert 750 km/h into metres per second.


Tom's dad is 3 times older than him. In 15 years the sum of Tom's and his dad's ages will be equal to 102. How old are Tom and his dad now?


You are given two equations: 3y-2x=11 and y+x=12. By solving simultaneously, what is the value of x and the value of 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