Answer:

Step-by-step explanation:
Brain correctly use a method of completing the square to solve the equation:

His First Step is to: Take the Constant Term to the Right Hand Side

The Next Step Would be to:
- Divide the Coefficient of x by 2
- Square It
- Add it to both Sides
In this case, the Coefficient of x = 7
- Divided by 2 =

- Squaring It, we have:

It is this number
that is added to both sides in the manner below:

Answer:
0=19
Step-by-step explanation:
Answer:
2.8 in a half years
Step-by-step explanation:
A = 6
B = 9
C = 15
D = ?
From A to B, 6 + 3 = 9
From B to C, 9 + 6 = 15
From C to D, 9 + x = ?
The first time, you added 3, for the second time, you added three to the three you are adding, making it 6. So for x, x = 6 + 3, which = 9
9 + 9 = 18
D = 18 should be your answer
hope this helps