Question

At how many points does the graph of `y=25x^2-10x+1` intersect the x-axis?

Answer 1

1 point

Explanation:

One of the standardised forms is `y=ax^2+bx+c`

where `x=(-b+-sqrt(b^2-4ac))/(2a)`

consider the part `" "b^2-4ac". "`

If this is negative then there is no intersection.
If it is 0 then there is just one
If it is greater than 1 then there are 2

`b^2-4ac" "->" "(-10)^2-4(25)(1)" "=" "0`

There is just 1.
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