Answer:
Option b is correct (8,13).
Step-by-step explanation:
7x - 4y = 4
10x - 6y =2
it can be represented in matrix form as
A=
X=
B=
i.e, AX=B
or X= A⁻¹ B
A⁻¹ = 1/|A| * Adj A
determinant of A = |A|= (7*-6) - (-4*10)
= (-42)-(-40)
= (-42) + 40 = -2
so, |A| = -2
Adj A=
A⁻¹ = / -2
A⁻¹ =
X= A⁻¹ B
X=
X=
X=
X=
x= 8, y= 13
solution set= (8,13).
Option b is correct.
Answer:
B. 7.3 years
Step-by-step explanation:
The question is wrong. The correct function is :
We have the function that represents the value of a piece of farm equipment after
years.
This means that when its original value is :
Now we want to calculate approximately when will its value be half its original value. Then, we write :
is half of its original value. We need to find
that satisfies the following equation :
Solving for :
⇒
Now we apply natural logarithm to each side of the equation :
Using logarithm properties :
⇒
⇒
≅
The correct option is B. 7.3 years