Question 73870: Write the equaition of the line through the points (-5,-7) and (-6,-4).
A) 12; y=11*x+69
B) 11; y=12*x+68
C) 11; y=11*x+69
D) 12; y=12*x+68
Found 3 solutions by checkley75, stanbon, rmromero:
Answer by checkley75(3666)   (Show Source):
You can put this solution on YOUR website! SLOPE (m) =(-4+7)/(-6+5)=3/-1=-3 NOW SUBSTITUTE ONE SET OF (X,Y) VAULES AND SOLVE FOR THE Y INTERSLOPE (b) THUS:
-7=-3*-5+b
-7=15+b
B=-7-15
b=-22
Y=-3X-22 ANSWER.
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Write the equaition of the line through the points (-5,-7) and (-6,-4).
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slope = [-4--7]/[-6--5]= 3/-1 = -3
The equation you want is y=mx+b
You are told y=-7 when x=-5 and you just figured out tht m=-3
so you can solve for "b", as follows:
-7 = -3(-5) + b
b = -22
EQUATION:
y = -3x - 22
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Checking:
(-5,-7): -7=-3*-5-22; -7 = 15-22; -7 = -7
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(-6,-4): -4 = -3*-6 - 22; -4 = 18-22; -4 = -4
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It checks.
Cheers,
Stan H>
Answer by rmromero(383) (Show Source):
You can put this solution on YOUR website!
Write the equaition of the line through the points (-5,-7) and (-6,-4).
A) 12; y=11*x+69
B) 11; y=12*x+68
C) 11; y=11*x+69
D) 12; y=12*x+68
You can solve this in two ways
Slope - intercept Formula
y = mx + b, where m = slope and b = y- intercept
Formula for the Slope (m)
m = ___________
Given two point , we solve for the slope
(-5,-7) = ( , )
(-6,-4) = ( , )
Substitute to the formula of the slope
-4 - (-7)
m = ___________
-6 - (-5)
-4 + 7
m = ___________
-6 + 5
3
m = ___________ or -3
-1
Then solve for b (y - intercept) by using the formula slope-intercept form
(x,y) = (-5,-7) or (-6,-4), m = -3
we use (-5, -7) for (x,y)
y = mx + b
-7 = -3(-5) + b
-7 = 15 + b
-7 - 15 = 15 - 15 + b
-22 = b
Now we have m = -3 and b = -22
Equation of the line
y = mx + b
y = -3x - 22
Equation of the line in standard form
y = -3x - 22
3x + y + 22 = 0
Note i don't know why the answer is not in the choices.
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