<u>t² -7 + 12t⁻² = 0</u>
Multiply each side by t² :
t⁴ -7t² + 12 = 0
This is a quadratic equation in the variable ' t² '.
For just a moment, to avoid confusion, let U = t².
Then the equation is
U² - 7U + 12 = 0
whence
(U - 4) (U - 3) = 0
and
U = 4 and U = 3 .
Now we can go back to ' t² ' in place of U :
t² = 4
<u>t = +2</u> and <u>t = -2</u>
t² = 3
<u>t = +√3</u> and <u> t = -√3</u>
Answer:
i think 3 seconds, sorry i don't know much about acceleration
Step-by-step explanation:
<h3>
Answer: Choice C. (x+1)(x-5)</h3>
We need to find two numbers that
- Multiply to -5 (last term)
- Add to -4 (middle coefficient)
Through trial and error, those two numbers are 1 and -5
- 1 times -5 = -5
- 1 plus -5 = -4
So this means x^2-4x-5 factors to (x+1)(x-5)
This is the same as (x-5)(x+1) since the order of multiplication doesn't matter.
Answer:
5 : 18 : 12
Step-by-step explanation:
Express the ratio B : C in fractional form, that is
= 
( cross- multiply )
6C = 4B ( divide both sides by 6 )
C = 
B = 
B , then
C = × 18 = 2 × 6 = 12
Hence
A : B : C = 5 : 18 : 12
