Ernest earned $8.55 per hour plus an additional $90 in tips waiting tables on Friday. He earned at least $160 in all.

What is the y-value to the solution of y = 5x -4 and y = 2x + 8

Fiesta28 [93]

Answer:

At the bottom!

Step-by-step explanation:

Put the two equations into the same standard form:

2x-y=8

-5x+2y=3

Now if you add the two equations up, guess what will happen?

You will "eliminate" the y variable, and only be left with the x variable.

Technically, you will get:

2x-y+2+28-5x+29+2y=8+23

-3x+20y=11

-3x=11

6 0

3 years ago

Answer and explain please

Sonja [21]

Answer:

You only need to add more tick marks and you also can multiply by three. 20 times 3 is 60 and 170 times 3 is 360.

8 0

3 years ago

Christian has a cookie recipe that yields four dozen cookies and calls for 2 1/4 cups white sugar and 3/4 cup brown sugar.cif ch

Paha777 [63]

The ingredients given are for 4 dozen cookies; however, Christian only want to make one dozen, meaning he requires only 1/4 the ingredients.

1/4 of 2 1/4 cups of while sugar is found the following way.

First, we write 2 1/4 as an improper fraction

$2\frac{1}{4}=2+\frac{1}{4}=\frac{9}{4}$

1/4 of this is

$\frac{9}{4}\times\frac{1}{4}=\frac{9}{16}$

Hence, Christian requires 9/16 cups of white sugar.

Similarly, the 1/4 of 3/4 cups of brown sugar is

$\frac{1}{4}\times\frac{3}{4}=\frac{3}{16}$

Hence, Chrisitan requires 3/16 cups of brown sugar.

Therefore, the total cups of sugar required is the sum of

$\frac{3}{16}+\frac{9}{16}=\frac{12}{16}=\frac{3}{4}$

3/4 cups of sugar.

7 0

1 year ago

A flashlight battery manufacturer makes a model of battery whose mean shelf life is three years and four months, with a standard

Vladimir [108]

Answer:

17,065 of those batteries can be expected to last between three years and one month and three years and seven months

Step-by-step explanation:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

In this problem:

I will calculate the time in months. Each year has twelve months.

Mean shelf life is three years and four months, with a standard deviation of three months. So

$\mu = 3*12 + 4 = 40$

$\sigma = 3$

Proportion lasting between three years and one month and three years and seven months:

This is the pvalue of Z when X = 3*12 + 7 = 43 subtracted by the pvalue of Z when X = 3*12 + 1 = 37

X = 43

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{43 - 40}{3}$

$Z = 1$

$Z = 1$ has a pvalue of 0.8413.

X = 37

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{37 - 40}{3}$

$Z = -1$

$Z = -1$ has a pvalue of 0.1587.

0.8413 - 0.1587 = 0.6826

Out of 25,000 batteries:

68.26% of the batteries are expected to last between three years and one month and three years and seven months.

0.6826*25000 = 17,065

17,065 of those batteries can be expected to last between three years and one month and three years and seven months

6 0

3 years ago

On a Saturday, Ellen and Carin agree to leave their homes at the same time, drive toward each other, and have lunch when they

sashaice [31]

Since Ellen drove a total of 80 miles, and for 2 hours.
Her speed is = 80/2 = 40 miles/hour

So Ellen drove for 40 miles/hour.

Since Carin drove 5 miles per hour faster than Ellen, the he drove = (40 + 5) = 45 miles/hour.

So Ellen drove 40 miles/hour and Carin drove 45 miles/hour

7 0

3 years ago