Direct and Indirect Variation Concepts

Alyssa introduces the concepts of direct and indirect (inverse) variation, explaining how they differ and providing examples to illustrate each. Direct variation is when two variables increase or decrease together, represented by y = Kx. Indirect variation is when one variable increases as the other decreases, represented by xy = K. Alyssa provides examples and problem-solving tips to help identify these variations in math problems.

What is another term for indirect variation?

• Direct variation

• Inverse variation

• Linear variation

• Constant variation

In the formula y = Kx, what does K represent?

• A coefficient

• A function

• A constant

• A variable

If y = 20 and K = 4 in a direct variation, what is x?

• 5

• 6

• 8

• 4

In a direct variation, if y increases, what happens to x?

• x decreases

• x becomes zero

• x increases

• x remains constant

What is the formula for indirect variation?

• y - x = K

• x + y = K

• y = Kx

• xy = K

In an indirect variation, if y increases, what happens to x?

• x increases

• x decreases

• x remains constant

• x becomes zero

Given x = 2 and y = 8 in an indirect variation, what is the constant K?

• 8

• 10

• 4

• 16

How can you determine if a set of data represents a direct variation?

• Check if x + y is constant

• Check if y/x is constant

• Check if xy is constant

• Check if x - y is constant

What should you do if given a pair of numbers and asked to find K for direct variation?

• Add the numbers

• Subtract x from y

• Divide y by x

• Multiply the numbers

In a direct variation, if x = 3 and y = 6, what is the constant K?

• 9

• 6

• 3

• 2