SOLUTION: are the lines parallel?explain. 2x+5y= -1 and 10y= -4x-20

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Question 509775: are the lines parallel?explain. 2x+5y= -1 and 10y= -4x-20
Found 2 solutions by Maths68, lwsshak3:
Answer by Maths68(1474) About Me  (Show Source):
You can put this solution on YOUR website!
2x+5y= -1
10y= -4x-20
Above lines are parallel ?
Equation of the line standard Form
y=mx+b
When two lines are parallel their slope will be same. So we will check whether the slope of the lines are same.
Line 1
==========
2x+5y= -1
Arrange above equation according the Equation of the line Standard form
5y=-2x-1
Divide by 5 both sides of the equation
5y/5=(-2x-1)/5
y=-(2x/5)-(1/5)
y=(-2/5)x+(-1/5)
Compare above equation with Equation of the line Standard Form
Slope = m = -2/5
Line 2
=========
10y= -4x-20
Arrange above equation according the Equation of the line Standard form
Divide by 10 both sides of the equation
10y/10= (-4x-20)/10
y=(-4x/10)-(20/10)
y=(-2x/5)-2
y=(-2/5)x-2
Compare above equation with Equation of the line Standard Form
Slope = m = -2/5
Conclusion
==========
Since slope of the both lines are same lines are parallel




Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
are the lines parallel?explain. 2x+5y= -1 and 10y= -4x-20
**
Write equations in standard form for straight lines: y=mx+b, m=slope, b=y-intercept
2x+5y= -1
5y=-2x-1
divide by 5
y=-2x/5-1/5
..
10y= -4x-20
divide by 10
y=-4x/10-2=-2x/5-2
..
As you can see, both equations have the same slope, -2/5, but different y-intercepts, so lines are parallel to each other.