x^2 - y = 14, y - 2 = 6x, solve these equations simultaneously

Make y the sbject of the second eqautiom y=6x+2. substitute this for the y in the first equation.the first equation now looks like x2 -(6x+2)=14. Open the brackets and subtract 14 from both sides. x2 -6x-16=0. Now we can factorise this to (x-8)(x+2)=0. from this we can deduce that x=8 and -2. We still need to find the answer to y since we know y=6x+2 (from first line) We can stustitute our answers to x in this. So When x=8, y= 50. When x=-2, y=-10

JP

Related Maths GCSE answers

All answers ▸

A circle has the equation x^2 + y^2 = 25. There is a point P on this circle with coordinates (4,3). A line is drawn tangental to the circle at point P. This line crosses the x axis at point Q. Find the co-ordinates of Q.


How do I factorise 3xy^2 – 6xy fully?


What are the two roots of the equation (4x-8)(x-3) = 0?


Find the equation of a straight line that passes through the points (2,7) and (5,3)