Points A(2,5) and B(7,8) lie on line L. What is the standard form of the equation of line L? (I got (3/5)x7=19/5 but it might be wrong)?
6 Answers
 PopeLv 79 months agoFavourite answer
There is disagreement over terminology, but this is how I see standard form:
ax + by = c
In this form, a should be nonnegative, and all three coefficients should be integers with no common divisors, if that is possible.
The equation you give has no y term, which makes it a vertical line, and neither of the given points satisfies the equation. So yes, it might be wrong.
Here is something that works for me:
A(2, 5), B(7, 8)
(8  5)(x  2)  (7  2)(y  5) = 0
3(x  2)  5(y  5) = 0
3x  6  5y + 25 = 0
3x  5y + 19 = 0 ... general form
3x  5y = 19 ... standard form
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 DavidLv 79 months ago
Points: (2, 5) and (7, 8)
Slope: 3/5
Equation: y = 3/5x + 19/5
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 ComoLv 79 months ago

m = 3/5
y  5 = (3/5) ( x  2 )
y = (3/5) x  6/5 + 5
y = (3/5) x + 19/5
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 Φ² = Φ+1Lv 79 months ago
(58)x  (27)y = 5×7  2×8
3x  (5)y = 19
3x  5y = 19
Source(s): The line through the points (x₁,y₁) and (x₂,y₂) in Standard Form {ax + by = c} is (y₁y₂)x  (x₁x₂)y = y₁x₂  x₁y₂ before simplification. Log in to reply to the answers
 Anonymous9 months ago
Let's use y = ax  b:
A(2, 5): 5 = a(2)  b, so b = 2a  5
B(7, 8): 8 = a(7)  b, so 7a  8 = b
Then 7a  8 = 2a  5
5a = 3
a = 3/5
Then b = 7(3/5)  8 = 21/5  8 = 21/5  40/5 = 19/5
So y = 3/5x + 19/5
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