Slope-Intercept Graphs

A dragon fly can beat its wings 30 times per second. Write an equation in slope-intercept form that shows the relationship between flying time in seconds and the number of times the dragonfly beats its wings. 

• y=30x
• y=x+30
• y=1/30x
• y=2x+7

A balloon is released from the top of a platform that is 50 meters tall. The balloon rises at the rate of 4 meters per second. Write an equation in slope-intercept form that tells the height of the balloon above the ground after a given number of seconds. 

• y=4x+50
• y=50x+4
• y=1/4x+50
• y=1/50x+4

Use the graph to find the slope of the line.  Tell what the slope means in this context. 

• m=.125 ; the diver ascends at a rate of .125 m/s
• m=8 ; the diver ascends at a rate of 8 m/s
• m=.125 ; the diver descends at a rate of .125 m/s
• m=8 ; the diver descends at a rate of 8 m/s

Identify the y-intercept. Tell what the y-intercept means in this context.

• b=-8 ; the diver starts ascending from 8 meters below the water's surface.
• b=10 ; the diver starts descending from 10 meters above the water's surface.
• b=-10 ; the diver starts descending from 10 meters below the water's surface.
• b=-10 ; the diver starts ascending from 10 meters below the water's surface.

Write an equation in slope-intercept form that represents the diver's depth over time.

• y=.125x+10
• y=.125x-10
• y=-10x+.125
• y=10x-.125

The cost of renting a sailboat at a lake is $20 per hour plus $12 for life jackets. Write an equation in slope-intercept form that can be used to calculate the total amount you would pay for using this sailboat.

• y=12x+20
• y=1/20x-12
• y=20x-12
• y=20x+12

Do these triangles have the same slope?

• No, they don't both sit on the line.
• Yes, they both have a slope of -3/2.
• Yes, they both have a slope of -2/3
• No, the orange triangle has a slope of -6/4 and the yellow triangle has a slope of -3/2

Do these triangles have the same slope?

• No, they are not similar triangles.
• Yes, they both have a slope of 1.

A driving range charges $4 to rent a golf club plus $2.75 for every bucket of golf balls you hit. Write an equation that shows the total cost c of hitting b buckets of golf balls.

• c = 2.75b + 4
• c = 2.75b
• c =  4b- 2.75
• c = 2.75b - 4

A camp charges families a fee of $625 per month for one child and a certain amount more per month for each additional child. Use the graph to write an equation in slope-intercept form to represent the amount a family with x additional children would pay.

• y = 625x + 225
• y = 225x 
• y = 225x + 625
• y =  625