Answer:
5 + sqrt(65), 5 - sqrt(65)
Step-by-step explanation:
x + y = 10
x×y = -40
so, two equations with 2 variables. using one equation to express one variable by the second. and then using the second equation to solve and calculate the second variable. and then by knowing the second variable we calculate the first.
=> x = 10 - y
=> (10-y)×y = -40
=> -1×(10-y)×y = 40
=> (y-10)×y = 40
=> y^2 - 10×y - 40 = 0
remember the solution for a quadratic equation
a×x^2 + b×x + c
is
x = (-b ± sqrt(b^2 - 4×a×c)/(2×a)
in our case
a = 1
b = -10
c = -40
and we used "y".
so,
y = (--10 ± sqrt((-10)^2 - 4×1×(-40))/(2×1) =
= (10 ± sqrt(100 + 160))/2 = (10 ± sqrt(260))/2 =
= (10 ± sqrt (4×65))/2 = 10/2 ± 2×sqrt(65)/2 =
= 5 ± sqrt(65)
=>
for y = 5 + sqrt(65), x = 10 - 5 - sqrt(65) = 5 - sqrt(65)
for y = 5 - sqrt(65), x = 10 - 5 + sqrt(65) = 5 + sqrt(65)
Answer:
254.5
Step-by-step explanation:
area of circle = pi (3.142) x 9squared
answer 254.5 or 81 pi
Answer:
55years
Explanation:
According to the given expression
FV = P +Prt
P is the initial deposit = $1000
FV is the future value = 4(1000) = $4000
r is the rate = 5.5% = 0.055
Required
Time t
Substitute the given values into the expression as shown;
FV = P +Prt
4000 = 1000 + 1000(0.055)t
4000 - 1000 = 55t
3000 = 55t
Swap
55t = 3000
t = 3000/55
t = 54.5years
t = 55years
This means it will take the deposit of $1000 55years to quadruple
Answer:
passive income
Step-by-step explanation:
