When a quadratic equation ax^2+bx+c has a double root, the discriminant,
D=b^2-4ac=0
Here
a=2,
b=b,
c=18
and
D=b^2-4ac=b^2-4*2*18=0
solve for b
b^2-144=0
=> b= ± sqrt(144)= ± 12
So in order that the given equation has double roots, the possible values of b are ± 12.
Answer:
It would be at a depth of 42 meters below the surface
Step-by-step explanation:
13(6)=78 -120+78=-42
Answer:
r = -3
Step-by-step explanation:
Add the like terms: 8r = -24
Isolate r by dividing each side by 8: r = -24/8
Simplify: r = -3
Hope this helps