I believe so yes this is correct I think
Answer:
The coordinates of B are (-2 , 9)
Step-by-step explanation:
A (8, 4)
M (3 , -1)
To calculate a midpoint you have to add the corresponding coordinates of each point and divide them by 2
(Ax + Bx) / 2 = Mx
(8 + Bx) / 2 = 3
8 + Bx = 3 * 2
Bx = 6 - 8
Bx = -2
(Ay + By) / 2 = My
( -1 + By) / 2 = 4
-1 + By = 4 * 2
By = 8 + 1
By = 9
The coordinates of B are (-2 , 9)
Answer: y - 5 = 0(x - 1)
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Explanation:
Recall that point slope form in general is written as such
y - y1 = m(x - x1)
where,
m is the slope
(x1,y1) is the point the line goes through
The given equation y = 7 can be written as y = 0x+7. So we see that this line has a slope of m = 0
Plug m = 0 along with the given point (x1,y1) = (1,5) into the point slope equation and we get
y - y1 = m(x - x1)
y - 5 = 0(x - 1)
which is the final answer
note: the equation in bold can be rearranged and simplified to get y = 5; however your teacher seems to want the answer in point-slope form, so we leave it as such.