Answer:
Step-by-step explanation:
9x⁴ – 2x² – 7 = 0
Let's say that u = x²:
9u² – 2u – 7 = 0
Factor:
(u – 1) (9u + 7) = 0
u = 1, -7/9
Since u = x²:
x² = 1, -7/9
x = ±1, ±i √(7/9)
Answer:
180
Step-by-step explanation:
Answer:
I think the answer is option A
Hello here is a solution :
<span>x² − 8x − 4 = 0.
</span><span>quadratic equation ax²+bx+c = 0 when : a=1 and b= -8 and c = -4
discriminant : d = b²-4ac d= (-8)²-4(1)(-4) =64+16 =70
x= (-b-rot(d))/2a </span>x'= (-b+rot(d))/2a .......conrinu