1 and 3
3x2 = 21 describes two single values, and does not have an x intercept. 3x2 = 21 ∴ x2 = 7 ∴ x = ±√7
3x2 + 17x + c = 0, rearranging gives c = -3x2 - 17x
Yes.
One factor is 3.
(3x-4)(x+5)
3x2 = 21 describes two single values, and does not have an x intercept. 3x2 = 21 ∴ x2 = 7 ∴ x = ±√7
3x2=6+38=44
3x2 + 17x + c = 0, rearranging gives c = -3x2 - 17x
In general, no.
y2=x3+3x2
No real roots.
Yes.
56
3
no 3x2=6 then 4x-15= -60 so 6 added with - 60 = -54
One factor is 3.
2