Find the value of Y so that the points (-2,5) and (8,y) lie on a line with slope -1/5
A) -5
B) -3
C) 3
D) 4
Show how to solve
The answer is 3
the point-slope equation of the line is
y-5 = -1/5 (x+2)
so now plug in x=8 and find the value of y.
So what is the answer
To find the value of Y that makes the points (-2, 5) and (8, y) lie on a line with a slope of -1/5, we can use the formula for slope:
slope = (change in y) / (change in x)
Given that the points (-2, 5) and (8, y) are on the line, we can substitute the coordinates into the slope formula:
-1/5 = (y - 5) / (8 - (-2))
Simplifying the formula further, we get:
-1/5 = (y - 5) / 10
Now, we can cross-multiply to solve for y:
-10 = 5(y - 5)
Distribute 5 on the right side of the equation:
-10 = 5y - 25
Move the constant term to the other side of the equation:
5y = -10 + 25
Combine like terms:
5y = 15
Finally, divide both sides of the equation by 5 to solve for y:
y = 3
Therefore, the value of y that makes the points (-2, 5) and (8, y) lie on a line with a slope of -1/5 is y = 3. Hence, the correct answer is option C) 3.