Answer:
A) x = 20
Step-by-step explanation:
ABCD is a rhombus, AC and BD are diagonals which intersect each other at point E.
Since, diagonals of a rhombus are perpendicular bisector.

To solve this problem, we need to first find the dimensions of the side of the blue and purple squares.
We're given that the purple (smaller) square has a side length of x inches.
We are also given that the blue band has a width of 5 inches.
Since the blue band surrounds the purple square on both sides, the length of the blue square is x+2(5)=x+10 inches.
The net area of the band is therefore the difference of the area of the blue square and the purple square, namely take out the area of the purple square from the blue.
Therefore
Area of band

[recall



or 20(x+5) if you wish.
Answer:
Length = 15
Width = 6
Area = 90
Step-by-step explanation:
Area of the rectangle = 
Lets factorise the polynomial


We know that Area = Length × Width
Let the length be (x + 3) & width be (x - 6)
Its given in the question that x = 12. So putting the value of x gives ,
Length = 
Width = 
Area = Length × Width = 15 × 6 = 90
Step-by-step explanation:
First I do it as separate equations 2x-7=0 and 5x+3=0. In this equation you get two answers so you first answer 2x-7=0
2x-7=0
+7 +7
2x=7
/2 /2
x=7/2
Then do 5x+3=0
-3 -3
5x=-3
/5 /5
x= -3/5
Then you can check by putting them back in.