Answer:
Mommy
Step-by-step explanation:
mommy mommy mommy mommy mommy
To complete a square for ax²+bx+c, you first make a=1.
in this case, a is already 1
move c to the right side: x²+14x=-47
next, add (1/2 of b)² to both sides, in this case, b=14, half of 14 is 7, so x²+14x+ 7²=-47+7²
the left side is now a perfect square: (x+7)²=2
x+7=√2 or x+7=-√2
x=√2-7, or x=-2-√7
Simplifying
8x + -10 = 62
Reorder the terms:
-10 + 8x = 62
Solving
-10 + 8x = 62
Solving for variable 'x'.
Move all terms containing x to the left, all other terms to the right.
Add '10' to each side of the equation.
-10 + 10 + 8x = 62 + 10
Combine like terms: -10 + 10 = 0
0 + 8x = 62 + 10
8x = 62 + 10
Combine like terms: 62 + 10 = 72
8x = 72
Divide each side by '8'.
x = 9
Simplifying
x = 9
To find the range of data, you first order the data least to greatest:
7, 12, 15
Then you subtract the smallest number from the largest:
15-7=8
The range is 8.
Mean is equal to sum/ number of values
27+3+2+25+5=62
62/5=12.4
Final answer: D, 12.4 years