Answer:
Step-by-step explanation:
We can factor out a 1 from -3 to get 
.
We know from simple arithmetic that 
.
So, our answer is 
Number of proper subsets = 2^number of elements- 1
= 2^n - 1
No of elements = 4
2^4-1 = 16-1 = 15
Yes, the rules of scientific notation are:
1. All non-zero digits are significant
2. Zeros in between non-zeros are significant.
3. Zeros to the left of the first non-zero number are NOT significant.
4. Zeros to the right of non-zero numbers are significant IF a decimal point is present.
P.S: if you need help with sig fig rounding, let me know.
If the value of a is positive, the line slopes upwards.
Use the Pythagorean Theorem of a² + b² = c² to solve for x.
x² + (x + 3)² = (√117)²
x² + x² + 6x + 9 = 117
2x² + 6x + 9 = 117
2x² + 6x + 9 - 117 = 0
2x² + 6x - 108 = 0
2x² + 18x - 12x - 108 = 0
2x(x + 9) - 12(x + 9) = 0
(2x - 12)(x + 9) = 0
x = - 9, 6
Length cannot be negative so you can't use - 9.
x = 6. Option C is your answer.
