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: (-∞,∞)
Step-by-step explanation: The line extends forever in both directions meaning that the endpoints will be negative infinity and infinity.
The answer is 1.87 pounds heavier. This is found out by subtracting 2.8 from 4.67.
Hope this helps!
Outcomes in a sample space :)
