General exponential equation
y = A(1+r)^x
where
A = initial value
r = rate increase (+) or decrease (-)
x = time period of the change
y = projected value
y = 300(1.05)^x
in this problem, x = years after 2017
we want to find an x that makes the value more than or equal to 650
650 <= 300(1.05)^x
Transpose all the terms in the left hand side of the equation. The equation then becomes,
8x² - 22x - 6 =0
Divide both sides of the equation by 2,
4x² - 11x - 3 = 0
In this equation, A = 4, B = -11, and C = -3
With the variables identified, the quadratic equation can be used to identify the roots,
x = (-B +/- √B² - 4AC) / 2A
The values of x in the equation are,
<em> x = 3 and x = -1/4
</em><em />Thus, the one of the answer to this item is the third choice, x = 3. <em>
</em>
Multiply $30 by .25 you get, it's $7.50so you subtract $7.50 from $30 and you get $22.50. Then multiply 2 (sweaters) by $22.50 and you get $45,but wait you still have to multiply that sales tax so you multiply .04 by $45 and you get $1.80, later you subtract $1.80 from $45 and you get $43.20(the cost of the two sweaters)
I did part1 only cuz' no I have no time left Sorry for the inconvenience
Answer:
The approximate number of years until the species is extinct will be 9 years
Step-by-step explanation:
We are given
The population of a species is modeled by the equation
where
t is the number of years
we have to find time when species extinct
we know that any species will be extinct only if population of that species becomes 0
so, we can set P(t)=0
and then we can solve for t
we can factor it
we get t value as imaginary for this equation
So,
the approximate number of years until the species is extinct will be 9 years
Answer:
y = 700x - 400
Step-by-step explanation:
A negative number represents an altitude below sea level.
Beginning: -400
y = mx + b
y = mx - 400
In 2 hours the altitude was now 1000 m.
1000 m - (400 m) = 1400 m
The altitude went up 1400 m in 2 hours. The rate of change is
1400/2 m/h = 700 m/h
The rate of change is the slope.
y = 700x - 400
