All categories

3 years ago

Consider the equation x^2-7x-8=0 and describe it's roots

Mathematics

1 answer:

statuscvo [17]3 years ago

3 0

Answer:

there are two different, real roots.

Step-by-step explanation:

The coefficients of this quadratic are {1, -7, -8}. Let's find the discriminant, b^2 - 4ac. In this case a = 1, b = -7 and c = -8 and so the discriminant value is

(-7)^2 - 4(1)(-8), or 49 + 32, or 81.

Because the discriminant is positive, we know immediately that there are two different, real roots.

We are not asked to find the roots, but let's do it anyway:

-(-7) ± √81

x = ------------------ => x = 8 and x = -2 (which are real and different from

2 one another).

You might be interested in

A machine is used to fill plastic bottles with bleach. A sample of 18 bottles had a mean fill volume of 2.007 L and a standard d

abruzzese [7]

Answer:

The 99% confidence interval for the difference between the mean fill volumes at the two locations is;

-0.1175665 L < μ₁ - μ₂ < 0.1295665 L

Step-by-step explanation:

The number of bottles in the sample at the first location, n₁ = 18 bottles

The mean fill volume, $\bar{x}_{1}$ = 2.007 L

The standard deviation, σ₁ = 0.010 L

The number of bottles in the sample at the second location, n₂ = 10 bottles

The mean fill volume, $\bar{x}_{2}$ = 2.001 L

The standard deviation, σ₂ = 0.012 L

The nature of the variance of the two samples = Equal variance

The confidence interval of the statistics, C = 99%

The difference between the mean

$\mu_1 - \mu_2 = \left (\bar{x}_{1}- \bar{x}_{2} \right )\pm t_{\alpha /2} \times \sqrt{\dfrac{\sigma _{1}^{2}}{n_{1}}+\dfrac{\sigma _{2}^{2}}{n_{2}}}$

(1 - C)/2 = (1 - 0.99)/2 = 0.005, the degrees of freedom, f = n₁ - 1 = 10 - 1 = 9

∴ $t_{\alpha /2}$ = 3.25

Therefore, we have;

$\mu_1 - \mu_2 = \left (2.007- 2.001 \right )\pm 3.25 \times \sqrt{\dfrac{0.01^{2}}{18}+\dfrac{0.12^{2}}{10}}$

Therefore, we have the difference of the two means given as follows;

-0.1175665 L < μ₁ - μ₂ < 0.1295665 L

8 0

3 years ago

5. Stacy bought 4 trays of eggs at sh.150 per tray.

blagie [28]

Answer:

Step-by-step explanation:

4 0

3 years ago

(e+1)x3=6 what will be the amount of e

Paul [167]

Answer:

e=1

Step-by-step explanation:

(e+1)×3=6

3e+3=6

3e=6-3

3e=3

e=3/3

e=1

3 0

3 years ago

Read 2 more answers

Y= 2x + 6 for x = 0,1,2,3,4

algol [13]

x=0 y=6

x=1 y=8

x=2 y=10

x=3 y=12

x=4 y=14

8 0

3 years ago

for a certain company, the cost function for producing x items is C(x)=40x+150 and the revenue function for selling x items is R

Mademuasel [1]

Answer :

Step-by-step explaation:

c(80) =40x80 +150 =3350 üretim için 80 parçanın maliyeti

satış için ise : R(80) 0.5(80-110)^2+6,050 = 456

3350-456=2983.95 kar ederler

5 0

3 years ago

Consider the equation x^2-7x-8=0 and describe it's roots​

Consider the equation x^2-7x-8=0 and describe it's roots