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Write an equation of line in point slope form containing (-1,1) and (4,-9)

Help!!!!!!!!!!!!!!!!!

User Guenter
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2 Answers

6 votes

Answer:

y - 1 = -2 (x + 1)

Step-by-step explanation:

point slope form: (y - y1) = m (x - x1)

m is the slope. To find m the formula is:

(y2 - y1) / (x2 - x1)

The given ordered pairs are: (-1,1) and (4,-9)

y2 is the y in the second ordered pair (-9)

y1 is y in the first ordered pair (1)

x2 is x in the second ordered pair (4)

x1 is x in the first ordered pair (-1)

= (-9 - 1) / (4 +1)

= -10/5

m = -2

Now plug m (-2), y1 (1), and x1 (-1) into the point slope form

y - 1 = -2 (x - -1)

y - 1 = -2 (x + 1)

User Eber Freitas Dias
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5.1k points
3 votes

9Answer: Y-1=-2(X+1) OR Y+9 = -2(X-4)

Step-by-step explanation:

Point slope form is Y-Y1=m(X-X1)

Slope (M) is (Y2-Y1)/(X2-X1)

SO M= (-9-1)/(4--1)

-10/5

M= -2

User Sunnyday
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4.7k points