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Which line has the same slope as the lone passing through (-4,-1) and (-1,-7)

1) 6x+3y=5
2)y=-1/2x-7
3)y=-2

User Jeff Lewis
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1 Answer

1 vote

Answer:

1) 6x+3y=5

Explanation:

1) First, find the slope of the line passing through (-4, -1) and (-1, -7). Use the slope formula
m = (y_2-y_1)/(x_2-x_1). Substitute the x and y values of the two points into the formula and solve:


m = ((-7)-(-1))/((-1)-(-4)) \\m = (-7+1)/(-1+4) \\m = (-6)/(3) \\m = -2

So, the slope is -2.

2) Now, identify the slopes of the lines in the options. We already know the slope of
y = -(1)/(2) x-7 is
-(1)/(2) since it is in slope-intercept form. y = -2 must have a slope of 0 since it's horizontal, and all equations with the format of y = a number are horizontal.

To find the slope of
6x + 3y = 5, isolate y to put the equations into slope-intercept form (
y = mx + b format), and whatever the coefficient of the x-term is will be the slope.


6x + 3y = 5\\3y = -6x+5\\y = -2x + (5)/(3).

So, the slope of the first option is -2. It matches the slope we calculated in the first step, so that must be the answer.

User Miaubiz
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3.1k points