solve y=3x+4, x=y+1

Equation 1) y=3x+4Equation 2) y=x+1
Rearrange equation 2 into terms of x as this is the simplest: x= y-1 (We do this by subtracting 1 off of each side to get X by itself)Substitute new equation 2 into 1: y=3(y-1)+4Expand the bracket by separately multiplying the factors inside the bracket by the value in front: y=3y-3+4Collect like terms: -1=2y (we do this by collecting the y's on the side where they will be positive and the single numbers on the other side and add together)Now we can solve y=-1/2 (we do this by dividing each side by 2 to get y on its own)Now we can substitute this value back into equation 2 to get: -1/2=x+1Subtract 1 off of each side to get -3/2 = x

CS

Related Maths GCSE answers

All answers ▸

Solve the simultaneous equations A and B: [A] 2x + y = 18 [B] x - y = 6


The price of a book is £4. In a sale the price is reduced by 30%. Work out the sale price.


Solve the quadratic 2x^2+7x+6 by completing the square


A stationary ball starts rolling down a hill, and after 5s it reaches a speed of 12m/s. From here the ground levels off, and the ball continues at this speed for 3 more seconds. Plot this on a velocity-time diagram.