All categories

2 years ago

Use the discriminant to determine the number of real solutions to the quadratic equation. 5a2+30a+45=0

Mathematics

1 answer:

Eddi Din [679]2 years ago

7 0

Answer:

Step-by-step explanation:

30^2 - 4(5)(45)

900 - 900

The discriminant works out to be 0, so there is one solution.

You might be interested in

Help me please! Literally don’t understand the question.

andrey2020 [161]

I think it's d hope it helps

6 0

2 years ago

Read 2 more answers

A researcher compares the effectiveness of two different instructional methods for teaching electronics. A sample of 138 student

yan [13]

Answer:

The 98% confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2 is (-8.04, 0.84).

Step-by-step explanation:

The (1 - <em>α</em>)% confidence interval for the difference between population means is:

$CI=(\bar x_{1}-\bar x_{2})\pm z_{\alpha/2}\times \sqrt{\frac{\sigma^{2}_{1}}{n_{1}}+\frac{\sigma^{2}_{2}}{n_{2}}}$

The information provided is as follows:

$n_{1}= 138\\n_{2}=156\\\bar x_{1}=61\\\bar x_{2}=64.6\\\sigma_{1}=18.53\\\sigma_{2}=13.43$

The critical value of <em>z</em> for 98% confidence level is,

$z_{\alpha/2}=z_{0.02/2}=2.326$

Compute the 98% confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2 as follows:

$CI=(\bar x_{1}-\bar x_{2})\pm z_{\alpha/2}\times \sqrt{\frac{\sigma^{2}_{1}}{n_{1}}+\frac{\sigma^{2}_{2}}{n_{2}}}$

$=(61-64.6)\pm 2.326\times\sqrt{\frac{(18.53)^{2}}{138}+\frac{(13.43)^{2}}{156}}\\\\=-3.6\pm 4.4404\\\\=(-8.0404, 0.8404)\\\\\approx (-8.04, 0.84)$

Thus, the 98% confidence interval for the true difference between testing averages for students using Method 1 and students using Method 2 is (-8.04, 0.84).

5 0

2 years ago

Coach Pettaway is buying basketball equipment for his team. He gets a

soldier1979 [14.2K]

First, let’s all acknowledge that whoever comes up with problems like this WANTS kids to hate math...smh

I’m sure there is a prettier way to solve this, but here’s what I did:

8(2.25) + 3(22.50) =
18 + 67.50 = 85.50 per “set” of balls/jerseys
400/85.50 = 4.678 = number of “sets” he can buy. Round down to 4 so we have room for tax.

85.5 x 4 “sets”= $342
Tax on 342 is 0.06 x 342 = 20.52

$342 + 20.52 = $362.52 spent

Basketballs = 4 sets x 8 balls per set= 32
Jerseys = 4 sets x 3 jerseys per set= 12

32 basketballs, 12 jerseys, $362.52 spent

3 0

2 years ago

Complete sequence. 4.15, 6.30, 8.45. How do I get answer?

azamat

They are going up by 2.15

6 0

2 years ago

Read 2 more answers

Given a circle with a radius of 0.85 meters, find the area of 1/3 of the circle. Use 3.14 for pi and round to the nearest hundre

olga_2 [115]

1/3 x pi x radius squared
1/3 x pi x 0.7225 = 0.7566002307

0.76 to nearest hundredth

7 0

2 years ago

Read 2 more answers