(X-5)2+3(X-5)+9 = 0
let expand the equation
(x)x2-(5)x2 + 3(x)-3(5) + 9 = 0
2x-10+3x-15+9=0
collect like terms
2x+3x-10-15+9 =0
5x-10-6 =0
5x-16=0
5x=0+16
5x=16
divide both side by 5 we have
x=16/5
It will take the seal 6.5 hours to swim 52 miles.
5x + 5x +3x (like terms)
13x-60=180
180+60=240
240/13=18.4615
X=18.4615
I hope this is correct.
(There are so many different ways to do math problems like this) I hope I could help... sorry if I didn’t.
Here, Sequence : -2, -6, -18, -54
Common Ratio = a₂/a₁ = -6/-2 = 3
As the expression is in negative sign, it's sequence will be -3ˣ
Where x = number of terms in the sequence [ By this rule, you can calculate the unknown nth number]
In short, Option C is your answer!!!!
Let me know, if you have some doubt.
