Solve these simultaneous equations 2y+x=8, 1+y=2x.

When solving simultaneous equations the first step is to take one of the equations and rearrange it to make one of the terms the subject. In this case lets take the equation 1+y=2x. Take the 1 over to the other side to make y the subject. y=2x-1. The next step is to substitute the expression for the term you have just worked out into the other equation that you didn't use at the beginning. In our case this gives us 2(2x-1)+x=8. Expand the brackets: 4x-2+x=8. Collect like terms: 5x=10. Simplify: x=2. Now we have one of the unknown values, we can substitute it back into one of the original equations to work out the final unknown. In our case: 1+y=2(2). Expand the brackets: 1+y=4. Collect like terms: y=3. Now we have both the answers x=2, y=3. You can check you answers by substituting the values back into the original equations and see if the two sides equal each other. 2(3)+(2)=8. 8=8. The answer is correct.

Answered by Lewis K. Maths tutor

2872 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Expand and simplify 3(m + 4) – 2(4m + 1)


Solve the following quadratic equation.


8^(3/4)*2^(x) = 16^(4/5). Work out the exact value of x.


Calculate the area of a circle with a diameter of 20mm


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences