<span>For a system of equations to have infinitely many solutions, the equations have to be lineary dependent, (i.e. one of the equations is a multiple of the other equation). For the given equation to have infinitely many solutions, the second equation have to be a multiple of the first equation.
The first equation can be rewritten as y - 2x = -5
The second equation is the first equation multiplied by 2, i.e. 2(y - 2x= -5) = 2y - 4x = -10
Therefore, the correct answer is -10 (option a).</span>
First and third one would work
The slope of the green line if the lines are perpendicular is -1/4
<h3>Perpendicular lines</h3>
For two lines two be perpendicular, the product of their slope must be -1. Let the slope of the red and green line be m1 and m2.
Given the following
Slope of red line = 4
According the definition
4m2 = -1
m2 = -1/4
Hence the slope of the green line if the lines are perpendicular is -1/4
Learn more on perpendicular lines here: brainly.com/question/1202004
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