How do you solve the simultaneous equations x^2+y=1 and -x+y=-1

First rearrange the second equation so that it's equal to y. You do this by adding x and y to both sides of the equation. You should then have y=x-1. Next you should sub y=x-1 into the first equation, x2+y=1. You should now be left with x2+x-1=1. This can be rearranged by subtracting 1 from each side to create the quadratic equation x2+x-2=0. This can be solved in which ever way you prefer; I would factorise it, leaving you with (x+2)(x-1)=0. Therefore x=-2 or x=1

CM

Related Maths GCSE answers

All answers ▸

A house is bought for £150,000 at the start of 2005. For 3 years it loses 10% of its original value per year. After this time it loses 10% per year. What was its value at the end of 2011/start of 2012?


An ordinary, fair sided dice is rolled 480 times. How many times is the number 3 expected?


Solve x^2 = 4(x - 3)^2


Equations