Solve the system of equations. 2x + 3y = 1 y = 3x + 15

1 answer:

6 0

Since y=3x+15
sub 3x+15 for y in other equation

2x+3(3x+15)=1
2x+9x+45=1
minus 45
11x=-44
divide 11
x=-4

sub
y=3x+15
y=3(-4)+15
y=-12+15
y=3

(-4,3)

You might be interested in

PLEASE HELP ME FAST!! THANK YOU!!

Neko [114]

Answer:

1.2, 2, 2.8

Step-by-step explanation:

Hey there,

15x=6

=> 5x=2, 3x=1.2, 7x=2.8

Hope this helps :)

5 0

3 years ago

The operations manager at a compact fluorescent light bulb (CFL) factory needs to estimate the mean life of a large shipment of

aliya0001 [1]

Answer:

The 95% confidence interval estimate for the population mean life of compact fluorescent light bulbs in this shipment is between 7,255 hours and 7,745 hours.

Step-by-step explanation:

We have that to find our $\alpha$ level, that is the subtraction of 1 by the confidence interval divided by 2. So:

$\alpha = \frac{1-0.95}{2} = 0.025$

Now, we have to find z in the Ztable as such z has a pvalue of $1-\alpha$ .

So it is z with a pvalue of $1-0.025 = 0.975$ , so $z = 1.95$

Now, find the margin of error M as such

$M = z*\frac{\sigma}{\sqrt{n}}$

In which $\sigma$ is the standard deviation of the population and n is the size of the sample.

$M = 1.96*\frac{1000}{\sqrt{64}} = 245$

The lower end of the interval is the sample mean subtracted by M. So it is 7500 - 245 = 7255 hours.

The upper end of the interval is the sample mean added to M. So it is 7500 + 245 = 7745 hours.

The 95% confidence interval estimate for the population mean life of compact fluorescent light bulbs in this shipment is between 7,255 hours and 7,745 hours.

7 0

3 years ago

What are the factors of x^2-8x-20

kipiarov [429]

Answer:

(x+2)(x−10)

Step-by-step explanation:

x^2-8x-20

Factoring means something like this:

(x+_)(x+_)

Add together to get -8

Multiply together to get -20