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Indicate the equation of the line through (2, -4) and having slope of 3/5.

It's more like a fill in the blank sort of thing. Please, I need help right away.

Indicate the equation of the line through (2, -4) and having slope of 3/5. It's more-example-1
User Wollmich
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2 Answers

2 votes
You can use point-intercept formula, m=3/5, y1=-4, x1=2
(y-y1)=m(x-x1)
y+4=3/5(x-2)
y+4=(3/5)x-6/5
y=(3/5)x-6/5-4
y=(3/5)x-6/5-20/5
y=(3/5)x-26/5 or y=0.6x - 5.2
User Pavel Franta
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8.2k points
4 votes

Comment
The slope is just read, and the point is used to determine b in the general equation.

General Formula
y = mx + b

Givens
m = 3/5
b is derived from (2,-4)

Derivation
y = 3/5 x + b The slope is solved.

y = -4 when x = 2
-4 = 3/5 2 + b
-4 = 3*2/5 + b
-4 = 6/5 + b Subtract 6/5 from both sides
-4 - 6/5 = b Multiply top and bottom of 4 by 5 to bring it to a common denominator of 5

(-4*5)/(1*5)-(6)/(5)=\text{b}
-26/5 = b

Final equation
y = 3/5 x - 26/5 <<<<<< answer

Discussion
If there are choices you should list them, because this question can be written other ways.
User Unruledboy
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8.5k points