SOLUTION: The equation of the line with y-intercept of 3 and perpendicular to the graph of 2x+y=5 is? This is an sample test questions for my math assessment test. I will be taking in a

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Question 94818: The equation of the line with y-intercept of 3 and perpendicular to the graph of 2x+y=5 is?
This is an sample test questions for my math assessment test. I will be taking in a few hours and this is my last question that I don't know how it works. I know the answer but I don't know how to get to that answer. Thank you very much!
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
The equation of the line with y-intercept of 3 and perpendicular to the graph of 2x+y=5 is?
:
y intercept occurs when x = 0, therefore the equation in the form y = mx + b
would be y = mx + 3
:
Now we want to find the slope (m) of the given equation:
Put equation in the slope/intercept (y = mx + b) form:
2x + y = 5
y = -2x + 5
The slope m = -2
:
Slope relationship between perpendicular lines is given as: m1*m2 = -1
Assume the m1 = -2 from the above equation,
find m2 (the slope of the perpendicular line) y = mx + 3
:
-2 * m2 = -1
Divide both sides by -1 and you have:
m2 = -1/-2
m2 = +1/2
:
The equation of the perpendicular line: y = 1%2F2x + 3
:
It will help you to memorize the perpendicular lines slope relationship
m1 * m2 = 1, and that y intercept occurs when x = 0