Question

Help with quadratic graphs asap!

I'm really not sure how to answer these questions to get the max marks. Its been my 3rd time posting these today yet I haven't received any help :( If anyone at all could help evn with one question it would mean a lot. Thanks

Answer 1

x= -0.25 and 1.25

x = -0.5 and 1.5

x = 0 and 1

x = -0.375 and 1.625

Explanation:

Given equation of the curve is

`y = 4x^2 -4x-1`

(i)

First equation
`4x^2 -4x-1 =0`

Here y = 0

In x-axis the value of y = 0

The graph cuts the x-axis at(-0.25,0) and (1.25,0)

So, x= -0.25 and 1.25

(ii)

`4x^2 -4x-1 =2`

here y = 2

The line y= 2 cuts the curve at (-0.5,2) and (1.5,2)

So, x = -0.5 and 1.5

Given equation of the curve is

`y= 3x^2-3x -1`

(i)

`3x^2-3x +2 =2`

`\Leftrightarrow 3x^2-3x -1 = -1`

Here y = -1

The line y = -1 cuts the curve at (0,-1) and (1,-1)

So x = 0 and 1

(ii)

`3x^2-3x -1 =x+1`

Here y = x+1

The line y -x =1 cuts the curve at (-0.375,0.5) and (1.625,2).

So x = -0.375 and 1.625