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3 years ago

Descompuneti in factori. x^2+4x-5=?

1 answer:

3 0

Assume that,
x^2+4x-5 = 0 .......(1)
Then, x^2+4x-5 = 0 x^2+5x-1x-5 =0
x(x+5)-1(x+5) = 0
(x+5) (x-1) = 0
We get x=-5 and x=1
Sub x=-5 in equ (1)
(-5)^2+4(5)-5 = 0
-25+20-5 = 0
-25+25= 0
0 = 0
Sub x=1 in equ (1) (1)^2+4(1)-5 = 0
1+4-5 = 0 5-5 = 0
0 = 0
Therefore x value is -5 and 1

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Find the value of g(16) for the function below

strojnjashka [21]

Answer:

Step-by-step explanation:

when you plug in 16 for x you will get -621.

$G(16)=27(16-39)\\G(16)=27(-23)\\G(16)=-621$

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3 years ago

It is 76°f at the 6000-foot level of a mountain, and 49°f at the 12,000-foot level of the mountain. write a linear equation to f

valina [46]

Answer:

$t(x) = 103 -0.0045x$

Step-by-step explanation:

We are given the following in the question:

Let the equation:

$t(x) = a + bx$

be the linear equation that represent temperature at an elevation x.

Temperature at 6000-foot level = 76 f

$76 = a + 6000b$

Temperature at 12000-foot level = 49 f

$49 = a + 12000b$

Solving the two equation, we get,

$76-49 = -6000b\\27=-6000b\\\\b = \dfrac{-27}{6000}\\\\b = -0.0045\\76 = a + (-0.0045)6000\\76 = a -27\\a = 76 + 27\\a =103$

Thus, we can write the linear equation as:

$t(x) = 103 -0.0045x$

5 0

3 years ago

Rob is saving to buy a new MP3 player. For every $16 he earns babysitting, he saves $9. On Saturday, Rob earned $96 babysitting.

Ivenika [448]

Answer:

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

Kareem made $273 for 13 hours of work. at the same rate, how many hours would he have to make to work to make $147?

klio [65]

Answer:

105

Step-by-step explanation:

273/13 × 5= 105

That's the correct answer

5 0

2 years ago

A professor wishes to discover if seniors skip more classes than freshmen. Suppose he knows that freshmen skip 2% of their class

KIM [24]

Answer:

We conclude that seniors skip more than 2% of their classes at 0.01 level of significance.

Step-by-step explanation:

We are given that a professor wishes to discover if seniors skip more classes than freshmen. Suppose he knows that freshmen skip 2% of their classes.

He randomly samples a group of seniors and out of 2521 classes, the group skipped 77.

Let p = percentage of seniors who skip their classes.

So, Null Hypothesis, $H_0$ : p $\leq$ 2% {means that seniors skip less than or equal to 2% of their classes}

Alternate Hypothesis, $H_A$ : p > 2% {means that seniors skip more than 2% of their classes}

The test statistics that will be used here is One-sample z proportion statistics;

T.S. = $\frac{\hat p-p}{{\sqrt{\frac{\hat p(1-\hat p)}{n} } } } }$ ~ N(0,1)

where, $\hat p$ = sample proportion of seniors who skipped their classes = $\frac{77}{2521}$

n = sample of classes = 2521

So, test statistics = $\frac{\frac{77}{2521} -0.02}{{\sqrt{\frac{\frac{77}{2521}(1-\frac{77}{2521})}{2521} } } } }$

= 3.08

The value of the test statistics is 3.08.

Now at 0.01 significance level, the z table gives critical value of 2.3263 for right-tailed test. Since our test statistics is more than the critical value of z as 2.3263 < 3.08, so we have sufficient evidence to reject our null hypothesis as it will fall in the rejection region due to which we reject our null hypothesis.

Therefore, we conclude that seniors skip more than 2% of their classes.

6 0

3 years ago