y=1-2x y=x2-3x-5

Question

i dont know how to do this simultaeneous equation

Answer 1

 

y=1-2x

y=x2-3x-5 

i assume its y=(x^2)-3x-5 where x^2 means x squared.

Not sure what level you are at, but as both y's are the same, set them equal to one another, ie 1-2x=(x^2)-3x-5

then set them equal to zero ie 0=(x^2)-x-4 

Then you can use the quadratic formula (if you know what that is) or you can factorise or complete the square. 

Note- will not factorise properly so quad formula or completing square needed. 

When using formula ->        a=1, b=-1, c=-4

1(+or-) sqrt 1^2 - 4*1*-4, all divided by 2

1 plus root 17 all over 2 or 1 minus root 17 all over 2 :)