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Can someone please help me? This is driving me insane!

Q: Find the value of y so that the line through the points has the given slope
(-4,y) and (-3,-5); slope: -7
A) -2 B) 6
C) 9 D) 2
also if you are able to, please explain why i keep getting 12 or -12!

User Idalina
by
8.1k points

1 Answer

6 votes
Hey there!

In order to figure this out, we can set up an equation using our slope given two points formula. We can set this equal to -7 as our slope has to equal this.

y2-y1/x2-x1 = -7

Plug in values:

-5-y/-3-(-4) = -7

Simplify

-5-y/-3 + 4 = -7

-5 - y/ 1 = - 7

-5 - y = -7

-y = -2

y = 2

Now, we can plug it back in to see if it works:

-5-2/-3-(-4) =
-7/-3-(-4) =
-7/-3+4 =
-7/1 =
-7

It works, so your value is D, 2. You're likely getting 12 or -12 because of issues with adding or subtracting, especially with the negatives, in this equation.

Hope this helps!

User Zealous System
by
8.1k points