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Need help quick.

1. Write the standard form of the line that contains a slope of 1/2 and y -intercept of 3. Include your work in your final answer.
2. Write the standard form of the line that passes through the given points.
(-1, -3) and (2, 1)

User Soomin
by
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1 Answer

5 votes

Hello there,

1. The standard form of a straight line with a slope and a y-intercept is as follows:


y=mx+b, where
m is the slope and
b is the y-intercept.

In this case, we have a slope of
(1)/(2) and a y-intercept of 3. Plugging in
(1)/(2) for
m and 3 for
b gives us:


y=(1)/(2)x+3

2. We are given two points. With these two points, we can find the slope with the formula for the slope to be:


m=(y_(2)-y_(1) )/(x_(2)-x_(1))

We can use the points and the corresponding values to solve for the slope:


m=(1-(-3))/(2-(-1))=(4)/(3)

We can plug
m into our equation:


y=(4)/(3)x+b

To find b, we simply plug in one of our points into this equation, and solve. I will use (2, 1) since both values are positive, but feel free to use (-1, -3) if you'd like:


1=(4)/(3)(2)+b


1=(8)/(3)+b


-(5)/(3)=b

Now plug
b into the equation.


y=(4)/(3)x-(5)/(3)

Hope this helps! :^)