Question

Could some please help me with this math question

Answer 1

y = 3x - 1

Slope intercept form is written in this format:
y=mx+b

m represents the slope
b represents the y intercept

You can clearly see that line intercepts the y axis at -1 so if you substitute that in:

y = mx - 1

You can easily find the slope by following this simple formula: rise/run

If you start at (0, -1) and try to get to (1, 2) then you go up 3 units and across 1 unit so the slope is 3/1 or 3. It’s not a negative slope since the line goes upwards and not downwards.

If you substitute the slope and y intercept you get:

y = 3x - 1

~~hope this helps~~

Answer 2

For this case we have that the equation of a line of the slope-intersection form is given by:
`y = mx + b`

Where:

m: It's the slope

b: It is the cut-off point with the y axis

To find the slope we look for two points through which the line passes:

We have to:

`(x1, y1) :( 1,2)\\(x2, y2): (- 1, -4)`

Thus, the slope is:

`m = \frac {-4-2} {- 1-1} = \frac {-6} {- 2} = 3`

We have then:

`y = 3x + b`

Substituting a point in the equation to find b:

`2 = 3 (1) + b\\2 = 3 + b\\b = 2-3\\b = -1`

Finally, the equation is:
`y = 3x-1`

Answer:

Option D