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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

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# Quadratic equations

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