What does changing the h variable do to the graph of a quadratic function

Molly's Custom Kitchen Supplies sells handmade forks and spoons. It costs the store $1.70 to buy the

scoray [572]

9514 1404 393

Answer:

7 forks
20 spoons

Step-by-step explanation:

Let x and y represent the numbers of forks and spoons made, respectively.

The cost of materials is ...

1.70x + 1.30y = 37.90

The revenue from sales is ...

5.60x + 5.40y = 147.20

You can solve these by any of your favorite methods. A graph is attached. It shows the solution is (x, y) = (7, 20).

They made 7 forks and 20 spoons.

_____

<em>Additional working out</em>

The equation coefficients are not "nice" multiples of each other, so elimination and substitution will require multiplying both equations by some numbers. If we're going to that trouble, we may as well use Cramer's Rule or a variation of the "cross multiplication method". The latter is relatively straightforward and can be easy to remember. It tells you the solution to ...

ax +by +c = 0

dx +ey +g = 0

is ...

1/(ae-db) = x/(bg-ey) = y/(cd-ga)

Here, that becomes ...

1/(1.70·5.40-5.60·1.30) = x/(1.30·(-147.20)-5.40·(-37.90))

= y/(-37.90·5.60-(-147.20·1.70))

1/1.9 = x/13.3 = y/38

x = 13.3/1.9 = 7 . . . number of forks

y = 38/1.9 = 20 . . . number of spoons

__

The above solution formula may be more easily remembered in terms of the cross-multiplication pattern that gives the method its name. When the coefficients are written in two rows of four, with the last being a repeat of the first:

a b c a
d e g d

each of the three denominators (of 1, x, and y) is the difference of products in adjacent columns, formed in an X fashion: ae-db, bg-ec, cd-ga. Note that the equations are written in "general" form, which is similar to "standard" form, but with all of the non-zero terms on the left of the equal sign. (This has the effect of changing the sign of the constants: 1.7x+1.3y=37.9 ⇒ 1.7x+1.3y-37.9=0)

8 0

2 years ago

Why is math literacy important?

Alex73 [517]

Answer:

Math literacy (also known as numeracy) means having the ability to problem-solve, reason, and analyze information.

Step-by-step explanation:

6 0

2 years ago

A Venn diagram is shown below: a Venn diagram showing two categories, A and B. In the A only circle is 1 and 2, in the B circle

erica [24]

The correct answer is {1, 2, 5, 6}.

A intersect B would be {3, 4}; the complement of this is everything else.

7 0

3 years ago

Read 2 more answers

Consider a chemical company that wishes to determine whether a new catalyst, catalyst XA-100, changes the mean hourly yield of i

kolezko [41]

Answer:

Null hypothesis: $\mu = 750$

Alternative hypothesis: $\mu \neq 750$

$t=\frac{811-750}{\frac{19.647}{\sqrt{5}}}=6.943$

$p_v =2*P(t_{4}>6.943)=0.00226$

If we compare the p value and a significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the actual true mean is significantly different from 750 pounds per hour.

Step-by-step explanation:

Data given and notation

Data: 801, 814, 784, 836,820

We can calculate the sample mean and sample deviation with the following formulas:

$\bar X =\frac{\sum_{i=1}^n X_i}{n}$

$s=\sqrt{\frac{\sum_{i=1}^n (X_i -\bar X)^2}{n-1}}$

$\bar X=811$ represent the sample mean

$s=19.647$ represent the standard deviation for the sample

$n=5$ sample size

$\mu_o =750$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

t would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses to be tested

We need to conduct a hypothesis in order to determine if the mean is different from 750 pounds per hour, the system of hypothesis would be:

Null hypothesis: $\mu = 750$

Alternative hypothesis: $\mu \neq 750$

Compute the test statistic

We don't know the population deviation, so for this case is better apply a t test to compare the actual mean to the reference value, and the statistic is given by:

$t=\frac{\bar X-\mu_o}{\frac{s}{\sqrt{n}}}$ (1)

t-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

We can replace in formula (1) the info given like this:

$t=\frac{811-750}{\frac{19.647}{\sqrt{5}}}=6.943$

Now we need to find the degrees of freedom for the t distirbution given by:

$df=n-1=5-1=4$

What do you conclude?

Compute the p-value

Since is a two tailed test the p value would be:

$p_v =2*P(t_{4}>6.943)=0.00226$

If we compare the p value and a significance level assumed $\alpha=0.05$ we see that $p_v$ so we can conclude that we reject the null hypothesis, and the actual true mean is significantly different from 750 pounds per hour.

4 0

3 years ago

If U = { 1 , 2 , 3 , 4 , 5 ,6 , 7 , 8 , 9 }. A={1 , 2 , 3 , 4 } , B= {2 , 4 , 6 , 8 } .Find

Zina [86]

Answer:

(A - B)' = {2, 4, 5, 6, 7, 8, 9}

(A n B) = {2, 4}

Step-by-step explanation:

Given the set :

U = { 1 , 2 , 3 , 4 , 5 ,6 , 7 , 8 , 9 }

A={1 , 2 , 3 , 4 } , B= {2 , 4 , 6 , 8 }

(A - B) = elements of A which are not in B

(A - B) = {1, 3}

(A - B)' = the complement of A - B ; element in the universal set which are not in A - B

(A - B)' = {2, 4, 5, 6, 7, 8, 9}

(A n B) = elements in both set A and set B

(A n B) = {2, 4}

4 0

2 years ago