Well you would have to round this 5 and above goes up. Since 1 is lower than 5 that would leave you at 6.37. 7 rounds up so that would change to 6.4. Lastly 4 would round down, So that would leave you with 6. Now 6 is the simplest form but if your looking for rounded to the nearest tenth the answer would be 6.4. If your looking for rounded to the nearest 100th place 6.37. But over all simplest form is 6.
If that is a rhombus as it says it is, then the diagonals are perpendicular to one another, meaning where they meet, they form right angles. Therefore, angle x is a 90 degree angle.
The answer to this question that you have me would be 5|x|-7=7 will equal to x=2