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Help help I don’t really get this???

Help help I don’t really get this???-example-1
User MrRay
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1 Answer

3 votes

Answer:

Question 4:
y=\displaystyle -(4)/(5)x

Question 5:
y=-5x-3

Explanation:

Hi there!

Linear equations are typically organized in slope-intercept form:
y=mx+b where m is the slope of the line and b is the y-intercept (the y-coordinate of the point where the line crosses the y-axis).

Question 4

1) Determine the slope (m)


\displaystyle m=(y_2-y_1)/(x_2-x_1) where two points that pass through the line are
(x_1,y_1) and
(x_2,y_2)

In the graph, two easy-to-identify points on the line are (-5,4) and (5,-4). Plug these into the equation:


\displaystyle m=(-4-4)/(5-(-5))\\\\\displaystyle m=(-4-4)/(5+5)\\\\\displaystyle m=(-8)/(10)\\\\\displaystyle m=-(4)/(5)

Therefore, the slope of the line is
\displaystyle -(4)/(5). Plug this into
y=mx+b as the slope (m):


y=\displaystyle -(4)/(5)x+b

2) Determine the y-intercept (b)

On the graph, we can see that the line crosses the y-axis when y is 0. Therefore, the y-intercept (b) is 0. Plug this into
y=\displaystyle -(4)/(5)x+b:


y=\displaystyle -(4)/(5)x+0\\\\y=\displaystyle -(4)/(5)x

Question 5

1) Determine the slope (m)


\displaystyle m=(y_2-y_1)/(x_2-x_1)

Two easy-to-identify points are (-1,2) and (0,-3). Plug these into the equation:


\displaystyle m=(-3-2)/(0-(-1))\\\\\displaystyle m=(-3-2)/(0+1)\\\\\displaystyle m=(-5)/(1)\\\\m=-5

Therefore, the slope is -5. Plug this into
y=mx+b:


y=-5x+b

2) Determine the y-intercept (b)

On the graph, we can see that the line crosses the y-axis at the point (0,-3). The y-coordinate of this point is -3. Therefore, the y-intercept (b) is -3. Plug this into
y=-5x+b:


y=-5x+(-3)\\y=-5x-3

I hope this helps!

User R J
by
4.2k points