All categories

2 years ago

-4x + 11y = 15 X = 2y Solve using substitution X = Y=

Mathematics

1 answer:

Virty [35]2 years ago

8 0

-4(2y)+11y=15, -8y+11y=3y=15: y=5

X=2(5)=10

To check your work -4(10)+11(5)=15
15=15

You might be interested in

A cereal brand is on sale $2 for 32 oz. If Sally spent $8 on the cereal, how many ounces did she purchase?

Lelechka [254]

Answer:

it would be 128 because 8 divded 2 is 4. 4 is the number of cereal boxes now multiply 4 x32 which would be 128

3 0

2 years ago

Read 2 more answers

3 pieces of wood have a total length of 32 m. The second piece is twice the size of the first and the third piece is 2 more mete

andreev551 [17]

Answer:

X + Y + Z = 32

X2 = Y

X3 + 2 = Z

X + X2 + X3 + 2 = 32

Make X alone

There is a 2 so we subtract 2 from both sides

X + X2 + X3 = 30

Add the X's up

X + X2 + X3 = X6

X6 = 30

Divide by 6

30 / 6 = 5

You are left with X=5

The first piece of wood has a length of 5

5 x 2 = 10

The second piece has a value of 10

5 x 3 + 2 = 17

The third piece is 17

Hope this helps. If you have any questions you may ask.

Step-by-step explanation:

5 0

3 years ago

What is the internal angle sum of a quadrilateral? (Hint: A quadirlateral has 4 sides.) OA) 90 OB) 180 OC) 360 OD 540

shtirl [24]

The internal angle sum of a quadrilateral is :

C. 360°

The sum of internal angles of a polygon is determined by a formula :

$\longmapsto (n - 2) × 180°$

where n represents number of sides.

In a quadrilateral there are four sides,

So, plugging 4 in the formula :

$(4 - 2) \times 180°$

$2 \times 180°$

$360°$

_____________________________

$\mathrm{ \#TeeNForeveR}$

5 0

2 years ago

Read 2 more answers

sara found a pair of jeans that was originally marked 85.00 but now have a clearance sticker for 54.50 what percent were the jea

Y_Kistochka [10]

U have to subtract from 85.00 from 54.00

5 0

2 years ago

he nutrition label for Oriental Spice Sauce states that one package of sauce has 1100 milligrams of sodium. To determine if the

MrRissso [65]

Answer:

The 99% confidence interval for the mean sodium content in Oriental Spice Sauce is between 454.67 milligrams and 1722.61 milligrams

Step-by-step explanation:

We have the standard deviation for the sample, so we use the t-distribution to solve this question.

The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So

df = 40 - 1 = 39

99% confidence interval

Now, we have to find a value of T, which is found looking at the t table, with 39 degrees of freedom(y-axis) and a confidence level of $1 - \frac{1 - 0.99}{2} = 0.995$ . So we have T = 2.7079

The margin of error is:

M = T*s = 2.7079*234.12 = 633.97

In which s is the standard deviation of the sample.

The lower end of the interval is the sample mean subtracted by M. So it is 1088.64 - 633.97 = 454.67 milligrams

The upper end of the interval is the sample mean added to M. So it is 1088.64 + 633.97 = 1722.61 milligrams

The 99% confidence interval for the mean sodium content in Oriental Spice Sauce is between 454.67 milligrams and 1722.61 milligrams

8 0

3 years ago