Ch. 7 First Quiz

Question 1

How to tell if something is direct or inverse

Answer 1

Solve for y
Direct is multiplication
Inverse is division

Question 2

y= kx

Answer 2

Direct

Question 3

Y= k/x

Answer 3

Inverse

Question 4

Joint Variation

Answer 4

Direct but with 2 or more things

Question 5

Remember to check work

Answer 5

Check work

Question 6

How to tell if a table is direct or inverse

Answer 6

Either plug the table into k=y/x for direct or plug the table into k=xy for inverse
If they all equal the same thing, they are direct/inverse

Question 7

k= y/x

Answer 7

Direct

Question 8

k=xy

Answer 8

Inverse

Question 9

How to multiply

Answer 9

Get each equation into its simplest form and cancel anything
Write an answer and solve each thing canceled for zero, then write x cannot equal that number

Question 10

How to divide

Answer 10

Keep, change, flip
Complete like a multiplication problem

Question 11

How to write an equation with x and y that varies inversely

Answer 11

Plug given x and y into k=xy and solve
Write the y=k/x equation with the new x
Solve for y

Question 12

How to write an equation with x and y that varies directly

Answer 12

Plug x and y into k=x/y and solve
Write the y=kx equation with the new x
Solve for y

Question 13

How to subtract

Answer 13

Get a common denominator by simplifying as much as possible
Subtract the top by distributing the negative and keep the bottom the same
Simplify
No x cannot equal

Question 14

How to add

Answer 14

Get a common denominator by simplifying as much as possible/multiplying the top and bottom
Add the top together and keep the bottom the same
Simplify
No x cannot equal

Question 15

How to solve an equation with an equal sign using the LCD

Answer 15

Find the LCD
Multiply each term by what the denominator needs to be the LCD
Cancel the denominators out
Solve for x

Question 16

If the equation is #*y= x, how to solve for y

Answer 16

y=x/#
Direct

Question 17

How to add three terms

Answer 17

Multiply the top of each by the two denominators that they don’t have
Solve each one by doing parentheses first and then distributing
Simplify as much as possible and keep the denominator the same

Question 18

How to rewrite an equation in k form

Answer 18

Choose a number you can take out of the x and that number to equal the denominator
Pick a number that will equal the original number when you subtract it before you take the number in front of the x out
Cancel the x+/- # and add the number in front of the x to the problem
The number after the x stays on top
The denominator is the same as the original denom.

Question 19

How to solve word problems

Answer 19

Write 4 labels
1: Total cost
2: Original Group; x
3: New Group/ x+# or x-#
4: Difference
Write equation
Total/x - Total/x+/- # = difference
***If the equation difference gets larger the equation will be Total/x+/-# - Total/x = difference