Answer:
A and C
Step-by-step explanation:
solving the equations
A
x² - 4 = 0 ( add 4 to both sides )
x² = 4 ( take square root of both sides )
x = ± = ± 2 ← required solution
B
x² = - 4 ← has no real solutions
C
4x² = 16 ( divide both sides by 4 )
x² = 4 ( take square root of both sides )
x = ± = ± 2 ← required solution
D
2(x - 2)² = 0 , then
x- 2 = 0 ( add 2 to both sides )
x = 2 ← not the required solution
Answer:
5.1 days
Step-by-step explanation:
Given in the question,
initial amount of substance = 34 grams
k-value = 0.137
To find the half life of this substance we will use following formula
here N(0) is initial amount of substance
t is time in days
Plug values in the formula
1/2 = e^{-0.137t}
Take logarithm on both sides
ln(1/2) = ln( e^{-0.137t})
ln(1/2) = -0.137t
t = ln(1/2) / -0.137
t = 5.059
t ≈ 5.1 days (nearest to tenths)
Answer:
4.5 sq. units.
Step-by-step explanation:
The given curve is
⇒ ...... (1)
This curve passes through (0,0) point.
Now, the straight line is y = 3x - 6 ....... (2)
Now, solving (1) and (2) we get,
⇒ (y - 3)(y + 2) = 0
⇒ y = 3 or y = -2
We will consider y = 3.
Now, y = 3x - 6 has zero at x = 2.
Therefor, the required are =
=
=
= 6 - 1.5
= 4.5 sq. units. (Answer)