Answer:
30. 2x²-x-1=0
or, 2x²-2x+x-1=0
or, 2x(x-1)+1(x-1)=0
or, (x-1)(2x+1)=0
so, x-1 = 0 or, x = 1
and 2x+1 = 0 or, 2x = -1 or, x = -1/2
so, x = 1 and 1/2
31. 3x²-14x=5
or, 3x²-14x-5=0
or, 3x²-15x+x-5=0
or, 3x(x-5)+1(x-5)=0
or, (x-5)(3x+1)=0
so, x-5=0 or, x=5
and 3x+1=0 or, 3x=-1 or, x=-1/3
so, x = 5 and -1/3
Answered by GAUTHMATH
A- Veronica —> v=5+2m
Total —> v+m=32
B- since you already know that to get veronica’s number of stuffed animals, you need to use v=5+2m, you need to substitute it in the total equation. So it’ll be:
(5+2m)+m=32
(5+2m) represents veronica’s stuffed animals
m represents Mariposa’s stuffed animals
C- Mariposa —> 9
Veronica —> 23
Answer:
Step-by-step explanation:
Since the incubation times are approximately normally distributed, we would apply the formula for normal distribution which is expressed as
z = (x - µ)/σ
Where
x = incubation times of fertilized eggs in days
µ = mean incubation time
σ = standard deviation
From the information given,
µ = 19 days
σ = 1 day
a) For the 20th percentile for incubation times, it means that 20% of the incubation times are below or even equal to 19 days(on the left side). We would determine the z score corresponding to 20%(20/100 = 0.2)
Looking at the normal distribution table, the z score corresponding to the probability value is - 0.84
Therefore,
- 0.84 = (x - 19)/1
x = - 0.84 + 19 = 18.16
b) for the incubation times that make up the middle 97% of fertilized eggs, the probability is 97% that the incubation times lie below and above 19 days. Thus, we would determine 2 z values. From the normal distribution table, the two z values corresponding to 0.97 are
1.89 and - 1.89
For z = 1.89,
1.89 = (x - 19)/1
x = 1.89 + 19 = 20.89 days
For z = - 1.89,
- 1.89 = (x - 19)/1
x = - 1.89 + 19 = 17.11 days
the incubation times that make up the middle 97% of fertilized eggs are
17.11 days and 20.89 days
Step-by-step explanation:
- 3over4 which is 75percent
