Answer:
x= -2/9
Step-by-step explanation:
2(x-2)/5=4x
2(x-2)=4x*5
2(x-2)=20x
x-2=20x/2
x-2=10x
-2=10x-x
9x= -2
x= -2/9
18x
Simple as that. 18 times however many times she cuts the grass
Answer:
-13, -3
15, 2.6
Step-by-step explanation:
x, y are the numbers
x = 5y + 2
x×y = 39
(5y + 2)×y = 39
5y² + 2y - 39 = 0
the solution of a quadratic equation :
y = (-b ± sqrt(b² - 4ac))/2a
a = 5
b = 2
c = -39
y = (-2 ± sqrt(2² - 4×5×-39))/2×5 =
= (-2 ± sqrt(4 + 780))/10 =
= (-2 ± sqrt(784))/10 = (-2 ± 28)/10
y1 = (-2 + 28)/10 = 26/10 = 2.6
y2 = (-2 - 28)/10 = -30/10 = -3
x1 = 5×2.6 + 2 = 13 + 2 = 15
x2 = 5×-3 + 2 = -15 + 2 = -13
Answer:
Step-by-step explanation:
no x-intercept/zero
Answer: A. 664
Step-by-step explanation:
Given : A marketing firm is asked to estimate the percent of existing customers who would purchase a "digital upgrade" to their basic cable TV service.
But there is no information regarding the population proportion is mentioned.
Formula to find the samples size , if the prior estimate to the population proportion is unknown :

, where E = Margin of error.
z* = Two -tailed critical z-value
We know that critical value for 99% confidence interval =
[By z-table]
Margin of error = 0.05
Then, the minimum sample size would become :

Simplify,

Thus, the required sample size= 664
Hence, the correct answer is A. 664.