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3 years ago

Please help me with these problems

Mathematics

1 answer:

S_A_V [24]3 years ago

8 0

Answer:

1.a=2

2. C x=2 and x=-3

Step-by-step explanation:

The standard form for the quadratic function is

ax^2 +bx+c

so we need to rewrite the function to be in this form

2x^2 -10 = 7x

Subtract 7x from each side

2x^2 -7x-10 = 7x-7x

2x^2 -7x-10 = 0

a =2, b= -7 c=-10

2. The quadratic formula is

-b ± sqrt(b^2 -4ac)

----------------------------

2x^2 + 2x=12

Lest get the equation in proper form

2x^2 + 2x-12 = 12-12

2x^2 +2x-12 =0

a=2 b=2 c=-12

Lets substitute what we know

-2 ± sqrt(2^2 -4(2)(-12))

----------------------------

2(2)

-2 ± sqrt(4+96)

----------------------------

2(2)

-2 ± sqrt(100)

----------------------------

-2 ± 10

----------------------------

-2 + 10 -2-10

----------- and --------------

4 4

8/4 and -12/4

2 and -3

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Helen [10]

Answer:

The answer would be A. 1 1/5

48/40 = 1 8/40

1 8/40 Simplify to 1 1/5

Hope this helps!

Step-by-step explanation:

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3 years ago

According to Scarborough Research, more than 85% of working adults commute by car. Of all U.S. cities, Washington, D.C., and New

tamaranim1 [39]

Answer:

The 99% confidence interval for the mean commute time of all commuters in Washington D.C. area is (22.35, 33.59).

Step-by-step explanation:

The (1 - α) % confidence interval for population mean (μ) is:

$CI=\bar x\pm z_{\alpha /2}\frac{\sigma}{\sqrt{n}}$

Here the population standard deviation (σ) is not provided. So the confidence interval would be computed using the t-distribution.

The (1 - α) % confidence interval for population mean (μ) using the t-distribution is:

$CI=\bar x\pm t_{\alpha /2,(n-1)}\frac{s}{\sqrt{n}}$

Given:

$\bar x=27.97\\s=10.04\\n=25\\t_{\alpha /2, (n-1)}=t_{0.01/2, (25-1)}=t_{0.005, 24}=2.797$

*Use the t-table for the critical value.

Compute the 99% confidence interval as follows:

$CI=27.97\pm 2.797\times\frac{10.04}{\sqrt{25}}\\=27.97\pm5.616\\=(22.354, 33.586)\\\approx(22.35, 33.59)$

Thus, the 99% confidence interval for the mean commute time of all commuters in Washington D.C. area is (22.35, 33.59).

8 0

3 years ago

debbie is a cook in a restaurant that is open 6 days a week. she is responsible for recording and monitoring the amount of money

dybincka [34]

The quantity of bread that Debbie uses each week on the average is = 54 loaves of bread

<h3>Calculation of weekly quantity of bread</h3>

The number of days the restaurant opens per week = 6 days.

The number of bread she uses everyday is = 9 loaves.

Therefore, the quantity of bread that Debbie uses each week on the average is = 6×9 = 54 loaves of bread.

Learn more about multiplication here:

brainly.com/question/4721701

#SPJ1

4 0

2 years ago

Find the value of 13 + (-7)

Vikki [24]

Answer:

Step-by-step explanation:

Before solve this you've to know that,

( + ) × ( - ) = ( - )

( + ) × ( + ) = ( + )

( - ) × ( - ) = ( + )

Let us solve now.

13 + (-7)

13 - 7

= 6

Hope this helps you :-)

Let me know if you have any other questions :-)

7 0

2 years ago

Read 2 more answers

Please help I have no clue what to do

max2010maxim [7]

Answer: m= 3

Step-by-step explanation:

Because 4xm=12 4x3=12 so the answer will be 3

8 0

3 years ago