Answer:
x²+(1/x²) = 47
Step-by-step explanation:
by identity : (a+b)² = a²+b²+2ab
(x+1/x)²= x²+(1/x)²+2(x)(1/x)
(x+1/x)²= x²+(1/x²)+2....(1)
since : (x²+1)/x = 7
(x²/x) +(1/x) = 7
x + (1/x )= 7
put the value for : x +(1/x) in (1) :
49 = x²+(1/x²)+2
x²+(1/x²) = 47
Answer:
4
Step-by-step explanation:
y=8x+4
y=mx+b where m=slope and b=y-intercept
b=4
To determine the number of cars that will be sold by the year 2020, we will use the equation,
N = (N1)(1 - r)^(t)
where N1 is the starting number of cars, r is the rate of the decrease, and t is the number of years from 2012. Substituting the konwn values,
N = (500)(1 - 0.028)^(8)
N = 398.38
The closest integer to the calculated value is 398. Thus, the answer is 398 cars.
Answer:
SA = 615.4 yd²
Step-by-step explanation:
The surface area (SA) of a sphere is calculated as
SA = 4πr² ← r is the radius
Here diameter = 14, thus r = 14 ÷ 2 = 7, then
SA = 4π × 7² = 4π × 49 = 196π = 196 × 3.14 ≈ 615.4 yd²