Answer:
B. 8 cm.
Step-by-step explanation:
The area of a rectangle is the length*width.
The area of the larger rectangle is 4*12=48.
The area of the smaller rectangle is 3*x=3x.
If the larger rectangle's area is twice that of the smaller rectangle, then we can say 48=2*3x.
Let's solve for x
48=2*3x
48=6x
x=8
Answer:

Step-by-step explanation:
In order to make d the subject of the formula, you need to isolate it.
- You started with d-7 = 4d + 3/e
- Move 4d to the left side by subtracting 4d from both sides to cancel it from the right so you have...
d - 7 = 4d + 3/e This will leave you left with -3d - 7 = 3/e
-4d -4d
- Then move over the -7 by adding 7 to both sides...
-3d - 7 = 3/e This will leave you left with -3d = 3/e + 7
+7 +7
- Finally to get d by itself divide both sides of the equation by -3 and you'll be left with...

- You can cancel out the 3 in the -3/3e and make it -1/e so your final answer will be

Answer:
40
Step-by-step explanation: