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3 years ago

find the equation of a line parallel to the line y=-9x+2 that passes through the point (5,5). GIve the answer in slope form

Mathematics

2 answers:

jolli1 [7]3 years ago

7 0

-9(m)=-1
m=1\9
5-Y=1\9(x-5)
-Y=1\9x-5\9-5
Y=-(1\9x-50\9)
y=-1\9x+50\9
9y=X+50

Nikitich [7]3 years ago

3 0

y = - 9x + 50

the equation of a line in slope-intercept form is

y = mx + c ( m is the slope and c the y-intercept )

y = - 9x + 2 is in this form with slope m = - 9

Parallel lines have equal slopes

y = - 9x + c is the partial equation of the parallel line

To find c substitute (5, 5 ) into the partial equation

5 = - 45 + c ⇒ c = 5 + 45 = 50

y = - 9x + 50 ← equation of parallel line

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Let X and Y be discrete random variables and E(X) and Var(X) are the Expected Values and Variance of X respectively.

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$\sum_{x,y}yP(X=x,Y=y)\\=\sum_{y}y\sum_{x}P(X=x,Y=y)\\\text{Taking Marginal distribution of y}\\=\sum_{y}yP(Y=y)=E[Y].$

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