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A line has a slope of -1/10

and includes the points (r, -10) and (-5, -9). What is the value of
r?

User Aajahid
by
8.0k points

1 Answer

4 votes

Answer:

To find the value of r, we can use the slope-intercept form of a linear equation, which is y = mx + b, where m represents the slope and b represents the y-intercept. Given that the slope of the line is -1/10, we can substitute this value into the equation as follows:

-10 = (-1/10)r + b

Next, we need to find the value of b. To do this, we can substitute one of the given points into the equation and solve for b. Let's use the point (-5, -9):

-9 = (-1/10)(-5) + b

-9 = 1/2 + b

To simplify further, we can convert 1/2 to a decimal:

-9 = 0.5 + b

Now, let's isolate b by subtracting 0.5 from both sides:

-9 - 0.5 = b

b = -9.5

Now that we have the value of b, we can substitute it back into our original equation:

-10 = (-1/10)r - 9.5

To solve for r, let's isolate r by adding 9.5 to both sides:

-10 + 9.5 = (-1/10)r

-0.5 = (-1/10)r

To get rid of the fraction, we can multiply both sides by -10:

(-0.5)(-10) = r

5 = r

Therefore, the value of r is 5.

Explanation:

User Sumeshk
by
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