With word problems!
need with 6 & 7.

Part 6) Option B $3.20

Part 7) Option C. 8,295 students

Step-by-step explanation:

Part 6)

Let

x -----> the cost of one hamburger

y ----> the cost of one soda

we know that

7x+3y=27.95 ------> equation A

5x+4y=23.40 ----> equation B

Solve the system by graphing

Remember that the solution by graphing is the intersection point both graphs

using a graphing tool

The solution is the point (3.2,1.85)

see the attached figure N 1

therefore

The cost of one hamburger is $3.20

Part 7)

Let

x -----> the number of students

y -----> the number of teachers

we know that

x=35y ------> equation A

x+y=8,544-12

x+y=8,532 -----> equation B

Solve the system by substitution

substitute equation A in equation B and solve for y

35y+y=8,532

36y=8,532

y=237 teachers

Find the value of x

x=35y ------> x=35(237)=8,295

therefore

The number of students is 8,295

rick has $1400 and sally has $1500

step-by-step explanation:

to find amount of money rick has after 10 years :

principal = $1000 , time = 10 years , rate = 4% annually

to find amount of money sally has after 10 years :

her friend gives to pay her $50 per year, therefore money she has after 10 years = 50 × 10 = $500

also, sally gets $1000 after 10 years,

therefore, total amount of money sally has after 10 years = 500 + 1000 = $1500

so, after 10 years : rick has $1400 and sally has $1500

when functions are first introduced, you will probably have some simplistic "functions" and relations to deal with, usually being just sets of points. these won't be terribly useful or interesting functions and relations, but your text wants you to get the idea of what the domain and range of a function are. small sets of points are generally the simplest sorts of relations, so your book starts with those.

step-by-step explanation:

state the domain and range of the following relation. is the relation a function?

{(2, –3), (4, 6), (3, –1), (6, 6), (2, 3)}

the above list of points, being a relationship between certain x's and certain y's, is a relation. the domain is all the x-values, and the range is all the y-values. to give the domain and the range, i just list the values without duplication:

domain: {2, 3, 4, 6}

range: {–3, –1, 3, 6}

(it is customary to list these values in numerical order, but it is not required. sets are called "unordered lists", so you can list the numbers in any order you feel like. just don't duplicate: technically, repetitions are okay in sets, but most instructors would count off for this.)

while the given set does indeed represent a relation (because x's and y's are being related to each other), the set they gave me contains two points with the same x-value: (2, –3) and (2, 3). since x = 2 gives me two possible destinations (that is, two possible y-values), then this relation is not a function.

note that all i had to do to check whether the relation was a function was to look for duplicate x-values. if you find any duplicate x-values, then the different y-values mean that you do not have a function. remember: for a relation to be a function, each x-value has to go to one, and only one, y-value.

state the domain and range of the following relation. is the relation a function?

{(–3, 5), (–2, 5), (–1, 5), (0, 5), (1, 5), (2, 5)}

i'll just list the x-values for the domain and the y-values for the range: