Question 509775
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