Susan C. answered 10/11/15
Tutor
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I love math, and I love to teach it.
First of all, you are given a line written as such: 4Y= X-8. You need to slove for "y" because you need to find the
slope of this line to determine what a perpendicular slope would be.
1. Divide both sides of the equation by the number next to "Y." Y= (X -8)/4 = x/4 -8/4 Y= 1/4 X -2
2. Therefore, its slope is the number next to "X." m= 1/4 = slope.
3. Next we are told that we are to write an equation that is perpendicular to the equation 4y= X -8.
This equation's slope is 1/4, but a line perpendicular to it would be the negative reciprocal. In other words, change 1/4 to 4/1 and make it negative, so it becomes -4/1. The perpendicular line must have a slope of -4/1.
4. Use the point-slope form to find your equation: y2-y1=m(X2-X1) .
5. Call the point given (5, -3) to be (X1,Y1). Substitute the values into the point-slope form equation.
y-(-3) = -4/1 (X-5)
Note: Since they want function notation, you will want to simplify this equation further.
6 Now solve for "Y." y +3= -4(X-5) To simplify use the distributive property: For example, a(x-b)= a*x-a*b .
7. Subtract 3 from both sides of the equation: Y= -4X +20 -3 y= -4X+ 17
8. Write it in function notation as such, f(X)=y , so f(X)= -4X+17. Answer