Answer:
Step-by-step explanation:
Given that A is a square matrix and A is idempotent

Consider I-A
i) 
It follows that I-A is also idempotent
ii) Consider the matrix 2A-I

So it follows that 2A-I matrix is its own inverse.
Take the coefficient of the x-term, half it, then square that. add this to both sides
x² + 16x. coefficient of x is 16. half of 16 is 8. 8²=64
x² + 16x + 64 =64. this is your answer but to continue
x² + 16x + 64 = 64
(x+8)² = 64
x+8 = ✓64
x+ 8 = ±8
x = 0 or -16
Answer:
x = 21/8
Step-by-step explanation:
Step 1: Write equation
x - 11 = 3 - 7(x - 1)
Step 2: Solve for <em>x</em>
<u>Distribute -7:</u> x - 11 = 3 - 7x + 7
<u>Combine like terms:</u> x - 11 = 10 - 7x
<u>Add 7x on both sides:</u> 8x - 11 = 10
<u>Add 11 on both sides:</u> 8x = 21
<u>Divide both sides by 8:</u> x = 21/8
Answer: 3
Step-by-step explanation: 2+2-1=3