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Write a linear function f with f(5)=-1 and f(0)=-5f(x)=____

User N Chauhan
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1 Answer

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Equation of a line

The slope-intercept of the equation of a line is given by:

y = mx + b

Where m is the slope and b is the y-intercept

The slope can be calculated with the formula:


\displaystyle m=(y_2-y_1)/(x_2-x_1)

Where (x1,y1) (x2,y2) are the points through which the line passes. We are given the points (5,-1) and (0,-5), thus:


m=(-5+1)/(0-5)=(-4)/(-5)=(4)/(5)

The equation of the line is:


y=(4)/(5)x+b

To determine the value of b, we use any of the given points, for example, (0,-5):


-5=(4)/(5)\cdot0+b=b

Thus, b=-5

The equation of the line is now fully determined:


y=(4)/(5)x-5

intercept

User Hallidave
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