$3x+y=19 \\
x+3y=1 \\ \\
\hbox{add the sides of the equations:} \\
3x+x+y+3y=19+1 \\
4x+4y=20 \\ \\ \hbox{divide both sides by 2:} \\
2x+2y=10$

The answer is d. 10.

6 0

4 years ago

charlie has 2 fair coins. he repeatedly tosses the pair of coins simultaneously (i.e., two tosses at a time), until he has seen

Serggg [28]

By using the trial method we get a total number of trials taken by Charlie to see both sides of both the coins is 4.

<h3>What is probability?</h3>

Probability is the name of the area of mathematics that deals with the examination of random events. The ratio of favorable occurrences to the total number of events is used to calculate an event's probability.

P(E) = F(E)/T (E)P(E)

It stands for the probability that an event will occur.

F(E) = Amount of favorable occurrences

Total number of trials (T(E))

Given that Charlie has 2 fair coins.

If he tosses the pair of coins simultaneously, then the number of samples can be HH, HT, TH, TT.

So to see both sides of both the coins he should toss the coin four times.

To know more about probability, visit:

brainly.com/question/12629667

#SPJ4

7 0

1 year ago

Lim (x+1) (3x^2-9)<br> X2

mafiozo [28]

Answer:

$\lim_{x \to 2} (x+1)(3x^2-9) = 9$

Step-by-step explanation:

Step 1: Write out limit

$\lim_{x \to 2} (x+1)(3x^2-9)$

Step 2: Evaluate

(2 + 1)(3(2)² - 9)

3(3(4) - 9)

3(12 - 9)

3(3)

5 0

3 years ago