Y^2-9y+81 can not be factored with any rational numbers
Answer:
x = ± 
Step-by-step explanation:
-8 - 8x^2= -31
Since this is a quadratic, it needs to be factored.
First, move the x to the other side:
-8 = 8x^2 - 31
Then, get the x alone by first adding 31:
23 = 8x^2
then dividing by 8:
x^2 = 23/8
Finally, square root both sides and remember the even roots property:
x = ± 
and simplify the root 8:
x = ± 
Note: This answer may have a mistake.
Answer:
third option
Step-by-step explanation:
Given
x² + 4x - 4 = 0 ( add 4 to both sides )
x² + 4x = 4
Using the method of completing the square
add ( half the coefficient of the x- term )² to both sides
x² + 2(2)x + 4 = 4 + 4, that is
(x + 2)² = 8 ( take the square root of both sides )
x + 2 = ±
= ± 2
( subtract 2 from both sides )
x = - 2 ± 2
Answer:
Part A:
Blueprint 10 inches ⇒ Actual 35 feet
Blueprint 20 inches ⇒ Actual 70 feet
Part B:
The cost of the cover is $857.5
Step-by-step explanation:
Part A:
∵ The drawing scale is 2 inches for 7 feet
∵ The length = 20 inches and the width = 10 inches
∴ The actual length = (20 × 7) ÷ 2 = 70 feet
∴ The actual width = (10 × 7) ÷ 2 = 35 feet
Part B:
∵ The cost per square foot = $0.35
∵ The area of the pool = 70 × 35 = 2450 feet ²
∴ The cost of the cover = 2450 × 0.35 = $857.5