Answer:
3. 2x + y = 21.
Step-by-step explanation:
3. The diagonals of a rhombus are perpendicular and bisect each other.
So the slope of line AC = -1/m
= -1 / 1/2 = -2.
AC has coordinates (5, 11) so using the point-slope form of a line:
y - 11 = -2(x - 5)
y = -2x + 10 + 11
2x + y = 21.
5. Line L:
x + 2y = 12
2y = -x + 12
y = -1/2x + 6
The slope is -1/2 so the slope m of M is -1 / -1/2 = 2.