How many x-intercepts does f(x)= x²+3x+3 have?

finlep [7]

25% because if you simplify the fraction, it would be 1/4 and that is equal to 0.25

3 0

3 years ago

All the fourth-graders in a certain elementary school took a standardized test. A total of 85% of the students were found to be

Aneli [31]

Answer:

There is a 2% probability that the student is proficient in neither reading nor mathematics.

Step-by-step explanation:

We solve this problem building the Venn's diagram of these probabilities.

I am going to say that:

A is the probability that a student is proficient in reading

B is the probability that a student is proficient in mathematics.

C is the probability that a student is proficient in neither reading nor mathematics.

We have that:

$A = a + (A \cap B)$

In which a is the probability that a student is proficient in reading but not mathematics and $A \cap B$ is the probability that a student is proficient in both reading and mathematics.

By the same logic, we have that:

$B = b + (A \cap B)$

Either a student in proficient in at least one of reading or mathematics, or a student is proficient in neither of those. The sum of the probabilities of these events is decimal 1. So

$(A \cup B) + C = 1$

In which

$(A \cup B) = a + b + (A \cap B)$

65% were found to be proficient in both reading and mathematics.

This means that $A \cap B = 0.65$

78% were found to be proficient in mathematics

This means that $B = 0.78$

$B = b + (A \cap B)$

$0.78 = b + 0.65$

$b = 0.13$

85% of the students were found to be proficient in reading

This means that $A = 0.85$

$A = a + (A \cap B)$

$0.85 = a + 0.65$

$a = 0.20$

Proficient in at least one:

$(A \cup B) = a + b + (A \cap B) = 0.20 + 0.13 + 0.65 = 0.98$

What is the probability that the student is proficient in neither reading nor mathematics?

$(A \cup B) + C = 1$

$C = 1 - (A \cup B) = 1 - 0.98 = 0.02$

There is a 2% probability that the student is proficient in neither reading nor mathematics.

6 0

3 years ago

Jason is playing a trivia game with his friends. At the end of each round, his score updates to the square of 1 less than the pr

mezya [45]

Answer:

8+n^2

Step-by-step explanation:

3 0

3 years ago

Read 2 more answers

What is the height of this triangle?

zavuch27 [327]

Answer:

XY (height) is approximately 20.8 feet

Step-by-step explanation:

let h = XY

tan60° = h/12

h = 12·tan60°

h = 20.78 ft

3 0

3 years ago

I need some help on this math problem, thanks so much

bekas [8.4K]

Answer:

The answer is C.

Step-by-step explanation:

Hit 'em with the Law of Sines.

sin(A)/a = sin(B)/b.

Let's say x is equal to "A", thus 5 is "a".

sin(x)/5 = sin(B)/b.

We could go for the obvious choice for "B", which would be the 90 degrees shown. To solve for the hypotenuse which will be "b", let's use the Pythagorean Theorem:

a^2 + b^2 = c^2

5^2 + 20^2 = c^2

25 + 400 = 425

sqrt(425) = about 20.6, which we can now substitute "b" with.

sin(x)/5 = sin(90)/20.6

sin(x)/5 = 1/20.6

sin(x)/5 = 0.04854...

sin(x) = 0.2427...

You can plug in sin^-1(0.2427) into your calculator, and you should end up with something like 14.047... which equates to answer choice C.

6 0

3 years ago