1. Write the equation that passes in standard form.
Day 15 – September 15th Objective:
To write and interpret direct variation equations
Write the equation that passes in standard form.
Write the equation in standard form.

2. Standard Form of a Linear Line
Standard Form: Ax + By = C ; where A,B, and C are whole numbers. Write the equation in standard form with integer coefficients.

3. X and Y intercepts
Finding x and y intercepts.
3x + 5y = 15

4. Direct Variation
A linear equation of the form y = kx, where k = 0, represents direct variation.
We call k the _____________________.
Solve y = kx for k.

5. For the following functions, determine if y varies directly with x
For the following functions, determine if y varies directly with x. If so, find the constant of variation and write the equation. x y -6 -2 3 1 12 4 x y 1 4 2 7 5 16

6. Writing a Direct Variation Equation
A dripping faucet wastes one cup of water if it drips for three minutes. The amount of water wasted varies directly with the amount of time the faucet drips. a.) Find the constant of variation, and write an equation to model the situation. b. How long would it take to waste 4½ cups of water?

7. Writing a Direct Variation Equation
For a given speed, the distance traveled varies directly with the time. Kate’s school is 5 miles away from her home and it takes her 10 minutes to reach the school. If Josh lives 2 miles from school and travels at the same speed as Kate, how long will it take him to reach the school?