Hello!
Let's solve !
⇒ (x - 3)² = 5
⇒ x² - 6x + 9 = 5
⇒ x² - 6x + 4 = 0
⇒ x = -(-6) ± √36 - 4(1)(4) / 2
⇒ x = 6 ± √20 / 2 = 6 ± 2√5 / 2
⇒ x = 3 ± √5
∴ The solutions are x = 3 + √5 and x = 3 - √5.
Answer:
answer 4950
Step-by-step explanation:
first divide6600by 100 &multiply by 25 ans. is 1650
subtract 6600 by 1650 ans. is 4950
Answer:
The end result is -1/(x + 1)
Step-by-step explanation:
In order to find the answer to this, we first need to factor the denominator. Since it is a quadratic, we try to find number that multiply to the last term (8) and add to the middle term (9). In this case, the numbers 8 and 1 would work. This allows us to use those numbers in parenthesis along with x as a fully factored form.
x^2 + 9x + 8 = (x + 1)(x + 8)
Now that we have this factored we can take the original equation and factor a -1 out of the top.
(-1)(x + 8)/(x + 1)(x + 8)
Since there is an (x + 8) on the top and bottom, we can cancel those.
-1/(x + 1)
The general way to work this out is to solve the general expression for
the remaining quantity versus half-life, using logarithms. But that's not
necessary with these numbers.
Look at the numbers:
-- 3 mg is 1/4 of 12 mg.
-- 1/4 is the product of (1/2) x (1/2).
-- So the 3 mg is what's left of 12 mg after 2 half-lives.
The 26 minutes must be two half-lives.
-- The half-life of that substance is 26/2 = <em>13 minutes</em>.
Go Maggie !
