There is a pattern of -2, -6, so the next number is 20.
Answer:
16
Step-by-step explanation:
Start by adding 9 to both sides, obtaining: √(x + 9) = 5.
Square both sides, obtaining: x + 9 = 25.
Subtract 9 from both sides: x = 16
Note that √(16+9) - 9 = -4, as required.
Answer:α
=
71
°
:
explain:
From trigonometry we have:
cos
α
=
7
21
7
=
21
cos
(
α
)
and:
α
=
a
r
c
cos
(
7
21
)
=
70.5
≈
71
∘
The answer is 100 degrees.
Answer:
$2936.79
Explanation:
The Formula for compounding interest:

F = final amount (we need to find this)
I = initial amount (900 + 250 + 300 + 1400 = $2850)
r = interest rate (1% = 0.01)
n = number of times interest applied per time period (360)
t = number of time periods elapsed (36 months = 3 years)

F = 2850(1.030454105)
F = $2936.79