Will mark as brainliest for these questions. joe owns a sandwich shop. he charges $10.00 for two sandwiches and one drink and $6.50 for one sandwich and one drink. how much does joe charge per sandwich? how much per drink? what is the solution of the system? use elimination. 3 − 2 = 5 −2 + = −3 producing a musical costs $8,000 plus $300 per performance. one sold-out performance earns $700 income. if every performance sells out, how many performances are needed to break even? in a chemistry lab, you have two vinegars. one is 20% acetic acid and one is 50% acetic acid. you want to make 200 ml of a vinegar with 30% acetic acid. how many milliliters (ml) of each vinegar do you need to mix together?

1.

Let the sandwich be represented by = x

Let the drink be represented by = y

As given, Joe charges $10.00 for two sandwiches and one drink, so equation becomes 2x+y=10    ....(i)

He charges $6.50 for one sandwich and one drink, so equation becomes x+y=6.50  ....(ii)

Subtracting (ii) from (i) we get

x=3.50

And as x+y=6.50

y=6.50-3.50=3.00

Hence, cost of a sandwich is $3.50 and a drink is $3.00

2.

the question is incomplete. coordinates are missing

3.

Let x represent the number of performances

cost = 8000+300x

revenue = 700x

To break even, the cost must be equal to the revenue.

so x=20

Hence, 20 performances are needed to break even.

4.

Let us take x for 20% material, y for 50% material

   ......... (1)

Accounting for volumes to use, x+y=200 or x=200-y ................ (2)

Putting the value of x in (1)

y=66.67

x=200-y = 200-66.67 =133.33

Hence, 133.33 ml of 20% acetic acid and 66.67% of 50% acetic acid is needed.

5=812a+9+3

step 1: simplify both sides of the equation.

5=812a+9+3

5=(812a)+(9+3)(combine like terms)

5=812a+12

5=812a+12

step 2: flip the equation.

812a+12=5

step 3: subtract 12 from both sides.

812a+12−12=5−12

812a=−7

step 4: divide both sides by 812.

812a /812 = -7/812

a= -1/116

so the answer is

a=   -1/116

correct answer is c. just did it

step-by-step explanation: