bob4000
Oct23-04, 10:13 AM
hey there reader
i have:
y=3x+11
y=2xsquared+2x+5
i have to solve these as they are represent a straight line and a curve respectively. so far i have:
3x+11=2xsquared+2x+5 at the intersection
;2xsquared-x-6=0
i factorised this and checked it to make sure it matched the above equation:
(2x+4)(x-2.5)
when i multiplied it out to check it i got: 2xsquared-x-6=0, which is alrite
when going on to solve x and y, i end up with:
x=-2
x=2.5
putting these into y=3x+11 i got:
y=5
y=18.5
finally giving the intersections of (-2,5) and (2.5,18.5)
however the answers given by the textbook from which the question was taken from, the intersections are (-1.5,6.5) and (2,17)
im really confused and would be much obliged for any help given
thank you
i have:
y=3x+11
y=2xsquared+2x+5
i have to solve these as they are represent a straight line and a curve respectively. so far i have:
3x+11=2xsquared+2x+5 at the intersection
;2xsquared-x-6=0
i factorised this and checked it to make sure it matched the above equation:
(2x+4)(x-2.5)
when i multiplied it out to check it i got: 2xsquared-x-6=0, which is alrite
when going on to solve x and y, i end up with:
x=-2
x=2.5
putting these into y=3x+11 i got:
y=5
y=18.5
finally giving the intersections of (-2,5) and (2.5,18.5)
however the answers given by the textbook from which the question was taken from, the intersections are (-1.5,6.5) and (2,17)
im really confused and would be much obliged for any help given
thank you