Answer:
D
Step-by-step explanation:
Given the 2 equations
4x - 5y = 18 → (1)
3x - 2y = 10 → (2)
Multiplying (1) by 3 and (2) by - 4, then adding will eliminate the x- term
12x - 15y = 54 → (3)
- 12x + 8y = - 40 → (4)
Add (3) and (4) term by term to eliminate x, that is
- 7y = 14 ( divide both sides by - 7 )
y = - 2
Substitute y = - 2 into either of the 2 equations and solve for x
Substituting into (1)
4x - 5(- 2) = 18
4x + 10 = 18 ( subtract 10 from both sides )
4x = 8 ( divide both sides by 4 )
x = 2
solution is (2, - 2 ) → D
The answer would be 25/54
Answer: d
Step-by-step explanation:
Answer: 
Step-by-step explanation:
Given :
re - writing the equation , we have
we need to find the value of a and b for which -2<x < 4 , this means that the roots of the quadratic equation are -2<x < 4.
The formula for finding the quadratic equation when the roots are known is :
- sum of roots(x) + product of root = 0
sum of roots = -2 + 4 = 2
product of roots = -2 x 4 = -8
substituting into the formula , we have:
, which could be written in inequality form as
comparing with , it means that :
Answer:
44.2 years
Step-by-step explanation:
If we assume the interest is compounded annually and the investment is a one-time deposit into the account, its value each year is multiplied by 1+6.25% = 1.0625. After n years, the value in the account will be ...
19000 = 1300·1.0625^n
Dividing by 1300 and taking logs, we have ...
log(19000/1300) = n·log(1.0625)
log(190/13)/log(1.0625) = n ≈ 44.24 . . . . years
It will take about 44.2 years for the account to reach $19,000.
