Linear Equations Word Problems

Linear Equations Word Problems

Slope-Intercept Form: y=mx + b

• m is the slope or rate of change

• b is the y-intercept, which is our starting point

• Rates can be described with phrases "each, for each, per..."

• Starting points sometimes use phrases like "initial, flat rate, one-time fee, ..."

Multiple Choice

It costs $4 per month to join a dance club plus a $30 startup fee.

In this situation, which number is the "b" value?

• $4

• $30

• $7.50

Multiple Choice

It costs $4 per month to join a dance club plus a $30 startup fee.

In this situation, which number is the slope?

• $4$

• $30$

• $\frac{15}{2}$

• $\frac{30}{4}$

Fill in the Blank

It costs $4 per month to join a dance club plus a $30 startup fee.

Write an equation in slope-intercept form to model the situation.

Fill in the Blank

Using the same situation as the previous slides, how much would it cost if you paid for 11 months? (It costs $4 per month plus a $30 startup fee.)

Fill in the Blank

An airplane 30,000 fee above the ground begins to descend at a rate of 2,000 feet per minute.

In this situation, which number is the slope?

The plane is descending!

• Descending means the height of the plane is going down.

• The altitude of the plane is decreasing 2,000 feet per minute.

• This would represent a slope of -2,000!