Help with any of the questions please!

Solve the following system.

PSYCHO15rus [73]

answers

y=2×2+3×-1 and x+ y= -1

Step-by-step explanation:

y =2×2+3x-1and x + y =1y= -2×2+3x-7 and x+y=-2x3x-1and x+y =-1

6 0

2 years ago

Researchers have noted a decline in cognitive functioning as people age (Bartus, 1990). However, the results from other research

kolbaska11 [484]

Complete Question

The complete question is shown on the first uploaded image

Answer:

a

Yes the researcher can conclude that the supplement has a significant effect on cognitive skill

b

$d = 0.5778$

c

The result of this hypothesis test shows that there is sufficient evidence to that the supplement had significant effect.The measure of effect size is large due to the large value of Cohen's d (0.5778 > 0.30 )

Step-by-step explanation:

From the question we are told that

The sample size is n=16

The sample mean is $M = 50.2$

The standard deviation is $\sigma = 9$

The population mean is $\mu = 45$

The level of significance is $\alpha = 0.05$

The null hypothesis is $H_o \mu =45$

The alternative hypothesis is $H_a \mu \ne 45$

Generally the test statistics is mathematically represented as

$z = \frac{M - \mu}{\frac{\sigma}{\sqrt{n} } }$

=> $z = \frac{50.2 - 45}{\frac{9}{\sqrt{16} } }$

=> $z = 2.31$

Generally the p-value is mathematically represented as

$p-value = 2 * P(Z > z )$

$p-value = 2 * P(Z > 2.31 )$

From the z-table

$P(Z > 2.31 ) = 0.010444$

=> $p-value = 2 * 0.010444$

=> $p-value = 0.021$

From the obtained values we see that $p-value < 0.05$

Decision Rule

Reject the null hypothesis

Conclusion

There is sufficient evidence to conclude that the supplement has a significant effect on the cognitive skill of elderly adults

Generally the Cohen's d for this study is mathematically represented as

$d = \frac{M - \mu}{\sigma }$

=> $d = \frac{50.2 -45}{9 }$

=> $d = 0.5778$

3 0

3 years ago

Help with the linear equations

IgorC [24]

Answer:

$y \: intercept = - 1 \frac{1}{2}$

Step-by-step explanation:

The y intercept form for the equation of a line is

$y = mx + c$

You should note that c represents the y-intercept of the line (where the line touches the y-axis)

$y = mx + c \\ \\ we \:were\: given \:the \:equation \:y = x - \frac{3}{2} \\ \\ therefore \: the\: value \:of \:c \:is\: - \frac{3}{2} \:or -1 \frac {1}{2}$

7 0

1 year ago

PLEASE HELP ITS EXTRA CREDIT AND I COULD REALLY USE IT !! BEING TIMED! for each of the following statements, determine if the st

bogdanovich [222]

A. True. We see this by taking the highest order term in each factor:

$f(x) = -3x(x-5)^3(x+2)^2 = -3x (x^3 + \cdots) (x^2 + \cdots) = -3x^{\boxed{6}} + \cdots$

B. True. Again we look at the leading term's degree and coefficient. f(x) behaves like -3x⁶ when x gets large. The degree is even, so as x goes to either ± ∞, x⁶ will make it positive, but multiplying by -3 will make it negative. So on both sides f(x) approaches -∞.

C. False. f(x) = 0 only for x=0, x = 5, and x = -2.

D. False. Part of this we know from the end behavior discussed in part B. On any closed interval, every polynomial is bounded, so that for any x in [-2, 5], f(x) cannot attain every positive real number.

E. True. x = 0 is a root, so f(0) = 0 and the graph of f(x) passes through (0, 0).

F. False. (0, 2) corresponds to x = 0 and f(x) = 2. But f(0) = 0 ≠ 2.

8 0

2 years ago

Use the given information to write an equation of the circle. center at (-7,-3), radius 2

Igoryamba

The equation of a circle is written as (x-h)^2 +(y-k)^2 = r^2

h and K are the center points of the circle and r is the radius.

replace the letters with the provided center and radius:

(x- (-7))^2 + (y- (-3))^2 = 2^2

Simplify:

(x+7)^2 + (y+3)^2 = 4

7 0

3 years ago