Review: y=mx+b

Review

"y= mx+b"

Linear Equation:

y = mx + b

Y= The Total value if we know the value of x

If x= 0, then Y= where we "begin"

Why do we need to know the

"y-intercept" ?

b=

Why do we need to know the

"y-intercept" ?

b=begin

Multiple Select

Why do we need to know the y-intercept?

• To find the total value when X=0

• To know where to begin plotting on a graph.

• To start looking for a pattern of how the total (y) value changes as x value changes

What Pattern is being followed?

The pattern of how y changes compared to x is called the "slope".

m =(▲y/▲x)

What is the change in the y value every time x changes?

The graph begins on (0,1) or (x=0, y=1).Then, as the x value goes up by 1, the y value increases by 1. (1,2)

m =(▲y/▲x) =( 1 / 1 )= 1

Linear equation:

Y= mx+b

If, b= 1

and, m=(▲y/▲x) = 1/1 = 1

then, Y= 1x + 1

or Y= x+1

Multiple Select

On this coordinate plain, what is the value of y?

• When x= 0, y=1

• when x= 1, y= 2

• When x=2, y= 3

• y= 1x+1

• y = x + 1

Multiple Choice

if y= 2x+5

What is the y-intercept?

• 2x

• 2

• 5

• 2x+5

Fill in the Blanks

Fill in the Blanks

Poll

Is finding the Y- intercept easy?

---------------

When given a graph, just find the place where the line crosses the y-axis at x=0.

When given an equation just look at the value for "b".

When given a table find the value for y when x=0.

When given a story, find out what the starting value is.

---------------

• Yes, Finding b is easy!

  Its the value when x=0

• NO, I don't know what "b" is.

Multiple Choice

if y= 3x+0,

What is the slope?

• 3/1

• 3x

• 0

• 3x+0

Multiple Choice

If y= 4x + 5

What is the value of y if x = 7 ?

• 20

• 28

• 33

• 35

Multiple Select

What equations matches the graph? y=mx+b

• y= 0.5x + 2

• y= (1/2)x + 2

• y= 0.5x + 3

• y= 2x + 3

• y= (1/2)x + 3