Equations from Relationships

Jamal uses 20 gallons of red paint. The equation y = 1.5x models this situation. How many gallons of white paint does Jamal use?

Select All That Apply: Fnd solutions to the equation

y = 12.5 x

• x = 1, y = 12.5

• x = 4; y = 45

• x = 10; y = 125

• x = 6; y = 75

The equation y = 0.75x describes the relationship between the number of cushions, x, and the number of yards of fabric, y, needed to cover those x cushions. How many yards of fabric are needed to cover 16 cushions?

• 12

• 13

• 16

• 20

Paintbrushes cost $3.50 each. Justin used the equation

y = 3.5x to find how many paintbrushes he can buy for an art project. Justin found the solution (2.2, 7.7) to the equation. Why is Justin’s solution not reasonable for this situation?

• Justin cannot spend $2.20 on paintbrushes.

• Justin cannot spend $7.70 on paintbrushes.

•  2.2 times 3.5 is not equal to 7.7

• Justin cannot purchase 2.2 paintbrushes.

Select All That Apply: Which expressions are equivalent to 55% of 300?

• 0.55 x 300

• 0.45 x 300

• 1.55 x 300

• 300 - (0.45 x 300)

A furniture designer builds a scale model of a chair. The height of the model is 4% of the height of the original chair. Which equation can be used to find the height of the model chair?

• y = 4x

• y = 1.04x

• y = 0.96x

• y = 0.04x

Write the equation for the table given

• y = 1/3x
• y = 3x
• y = 1/2x
• x = 3y

In the equation y = 14x, what is the constant of proportionality?

• y
• x
• 14

What is the formula for a proportional relationship?

• y=kx
• y=k/x
• z=ykx
• y=ky

If the constant of proportionality is 10, which of the following is the correct proportional equation?

• 10=kx
• 10=k
• y=10k
• y=10x