Question

Algebra 1 Help: Finding Slope and Intercept, creating equations in slope-intercept form.

(Problems #11, 17, 21, 23, 25, 29, 33.) - PICTURES INCLUDED

Answer 1

@marissalovescats @girlnotonfire @tayromo Do think you guys could help me?

Answer 2

The slope form is y = mx + c

So, compare the equation to find m (slope). The constant term is the intercept

Answer 3

e.g. y = 3x + 4 means that the slope is 3 and the intercept is 4.

Answer 4

if m = 1 and intercept = -1 then the equation is
y = 1.x - 1 = x -1

Answer 5

Here' help for #11.

This is the slope-intercept form of the equation of a line.
\(y = mx + b\)
Where m = slope, and b = y-intercept.

Once you have an equation in that form, just read off the slope and the intercept.

For example, if the equation is

\(y = \color{red}4x + \color{green}2\)

The the \(slope = \color{red}{4}\), and
the \(y-intercept = \color{green}{2}\)

Answer 6

Problems 17 and 21 are the above procedure in reverse.
For example, if the slope is 6 and the y-intercept is -4, then the equation is:
y = 6x - 4

Answer 7

The picture dosen't show 29 and 33.

Answer 8

I'll post the picture for 25, 29 and 33 right now. Thank you both so very much!

Answer 9

Are you still there? I post the picture for 25, 29, and 33.

Answer 10

What about 23 and 25?

Answer 11

Problems 22 to 27 are done this way.
You are shown a graph. From the graph you need to find the slope and the y-intercept.
Then you just use the slope and the y-intercept to write the equation as
y = mx + b

Answer 12

The quicker thing to read off the graph is the y-intercept.
To do that, just find the value at which the line crosses the y-axis.

Answer 13

For example, in the graph above, the y-intercept, b, is 3.

Answer 14

The next thing you need to find is the slope.

Answer 15

So for 23 would the y-intercept be -3?

Answer 16

Correct.

Answer 17

Now I'll tell you how to read the slope off a graph.

Answer 18

Okay

Answer 19

First, you must pick two points on the straight line.
In theory, any two points will do, but in reality, this works best if the points are on an intersection of grid lines. This way you can read the points much more easily.

Answer 20

Using problem 25 as an example, the point on the y-axis, (0, 4) is on the grid itself.
Another point can be the point where the line crosses the x-axis. That point is (0, 2).

Answer 21

Now that we have chosen two points, we need to find the slope.

Answer 22

The slope is a ratio.
A ratio is a comparison of numbers using division.
The slope is the rise over the run.
We divide how much we go up or down from one point to the other, by how much we go right or left from one point to the other.

Answer 23

I'll draw it and explain it with the drawing.

Answer 24

okay

Answer 25

We need to go from one point to the other.
We can't go on the line. We are only allowed to walk vertically and horizontally.

Answer 26

Let's say we start at the point where the line crosses the x-axis.