3 years ago

-7r2 + 7r + 2 = 2 Find Discriminant

Mathematics

2 answers:

GarryVolchara [31]3 years ago

7 0

I think r=0 I think that’s the answer

victus00 [196]3 years ago

5 0

Answer:

r = 1 , 0

Step-by-step explanation:

-7 $r^{2}$ + 7r + 2 = 2

-7r(r-1)=2-2

-7r(r-1)=0

r-1=0

r=1

You might be interested in

Celia needs 75% of the marks in an exam to pass. She gets 4/5 of the marks. Does she pass the course? Show your working to justi

kari74 [83]

Answer:

Yes, she passes with 80%

Step-by-step explanation:

4 divided by 5 = 0.8

0.8 multiplied by 100 = 80%

80% is greater than the required 75% needed to pass

5 0

1 year ago

Read 2 more answers

A light bulb has a lifetime X that is exponentially distributed with a mean 340 hours. Find the probability that the bulb lifeti

LUCKY_DIMON [66]

Answer:

0.7026

Step-by-step explanation:

Let X denote the lifetime of light bulb. Given $X \sim Exp(\lambda)$ where the mean is $E(X) = 340 =\frac{1}{\lambda} \implies \lambda = \frac{1}{340} = 0.00294$ .

Recall that,

$\displaystyle P(X>x) = 1 - \int_0^x e^{-\lambda x} = 1 - (1 - e^{-\lambda x} = e^{-\lambda x}$

$\displaystyle P(X>220 | X>100) = \frac{P(X>220,X>100)}{P(X>100)} = \frac{e^{-\lambda \times 220}}{e^{-\lambda \times 100}} = \frac{0.5236}{0.7452} = 0.7026$