Given the two equations [1](3x + 4y = 23) and [2](2x + 3y = 16), find the values of x and y

One way to find the values of x and y is to substitute the value of x into one of the equations. To sub in x we need to rearrange an equation to get x on its own. We can change the second equation to x = (16 - 3y)/2. We then sub this into equation 1 and get3[(16 - 3y)/2] + 4y = 23. Expanding this out gets 24 - (9/2)y + 4y = 23. -(9/2)y + 4y = -1 -1/2y = - 1 -y = -2 y = 2. This can then be substituted back into an equaiton to get x. Subbing back into equation 1 gets 3x + 8 = 23. 3x = 15 x = 5This can then be verified by subbing in our values back into equation 2 to check that our answers are correct.

SH
Answered by Stephen H. Maths tutor

3175 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

A ball, dropped vertically, falls d metres in t seconds. d is directly proportional to the square of t. The ball drops 45 metres in the first 3 seconds. How many metres does the ball drop in the next 7 seconds?


i) The point A on a graph is (6,-7), and point B is (3,5). Calculate the equation of the straight line that passes through both A and B. ii) Does the line pass through the point C (-2,26)?


A group of 55 students were asked if they had a cat or a dog. 11 were known to own both, 18 said they owned only a dog, and 34 said they owned at least a cat. Give the probability that a student has neither as a fraction in its simplest form.


How do I solve simultaneous equations using the substitution method?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning