Solve the following simultaneous equations 7x - 6y =38 and 3x + 9y =-3

To solve these equations you first want to eliminate the same variable from each equation. In this question it is easiest to eliminate Y, to do this we will times equation 1 by 3 to get 21X-18Y=114 and equation 2 by 2 to get 6X+18Y=-6. Now, when you add both of or new equations together you get 27X= 108 which leads to X=4. We can now substitute X=4 into our 1st equation to find a value for Y. So, 7(4) -6Y= 38 implies that -6Y=10 hence Y=-5/3. To check your answer you can substitute X=4 and Y=-5/3 into the second equation to check the answer works, which it does.

IR
Answered by Isabelle R. Maths tutor

3208 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

s^2 - 2s - 24 = 0


Solve algebraically: 6a + b = 16 ..... 5a - 2b = 19


Simplify √48


Sophie had 3 piles of coins, A, B and C. Altogether there was £72. Pile B had twice as much as pile A. Pile C had three times as much as pile B. How much money was in Pile C?


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