Word Problems Point-Slope

The population of a city increases by 4000 people each year. In 2025, the population is projected to be 450,000 people. What is an equation that gives the city's population y (in thousands of people) x years after 2010?

• y = 4x + 450

• y - 450 = 4(x - 15)

• y - 15 = 4(x - 450)

• y = 4x + 15

Which application should you use to solve the given problem?

• Slope-Intercept

• Standard Form

• Point & Slope

• Two Points

Answer explanation

 $m=0.30\ \ \ \left(120,51\right)$ 

Which application should you use to solve the given problem?

• Slope-Intercept

• Standard Form

• Point & Slope

• Two Points

Answer explanation

 $m=-0.2\ \ \ \left(8,13.4\right)$ 

Which application should you use to solve the given problem?

• Slope-Intercept

• Standard Form

• Point & Slope

• Two Points

Answer explanation

 $m=850\ \ \ \left(9,\ 307650\right)$ 

Find the rate of change.

Then write the point-slope equation.

• -2 minutes per gallon

  y - 80 = -2 (x - 10)

• -20 minutes per gallon

  y - 80 = -20 (x - 10)

• -2 gallons per minute

  y -80 = -2 (x - 10)

• -20 gallons per minute

  y - 80 = -20 (x - 10)

This problem:

• gives you a rate of change (slope) and a starting point (y-intercept)

• relates two different objects

• gives you a rate of change (slope) and a sample point (x,y)

This problem:

• gives you a rate of change (slope) and a starting point (y-intercept)

• relates two different objects

• gives you a rate of change (slope) and a sample point (x,y)

This problem:

• gives you a rate of change (slope) and a starting point (y-intercept)

• relates two different objects

• gives you a rate of change (slope) and a sample point (x,y)

An airplane at 30,100 feet above the ground begins descending at the rate of 2,150 feet per minute. Write and solve a linear equation to find how many minutes it will take the plane to reach the ground.

• slope intercept form

• standard form

• point slope form

• two points

A candlestick burns at a rate of 0.2 inches per hour. After eight straight hours of burning, the candlestick is 13.4 inches tall. Write and solve a linear equation to find the original height of the candle.

• slope intercept form

• standard form

• point slope form

• two points