To prove a rhombus you need to show that the sides are congruent and the diagonals are perpendicular.
Sides:
















≅
≅
≅ 
Diagonals:
Use the slope formula: 


= -1


= 1
Slopes are opposite reciprocals so they are perpendicular.
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All of the sides are congruent and the diagonals are perpendicular so RMBS is a rhombus.
I no learn yet. buttttttt what ever I don't care
Answer:
I saw this is recent so I cant explain to much because I dont know if your timed but 1.4 is equal to your number. all you got to do is 2.1 divided by 1.5
Step-by-step explanation
The 4th option.
The values with no x or y attached are the y intercept
6x - 7y = 21
Subtract 6x from both sides
6x - 7y - 6x = 21 - 6x
-7y = 21 - 6x
Divide both sides by - 7
-7y/-7 = 21/-7 - 6x/-7
Y = -3 +6x/7
The why intercept, -3 is the same as the one in the question