X² = 16
the way to isolate your x variable is to square root both sides
√x² = √16
x = <span>± 4
so your answers are 4 and -4</span>
Answer:
a) The maximum amount of water the aquarium can hold is 1728 in³.
b) The cover has to be 624 in² big.
Step-by-step explanation:
a) The maximum volume of water that the aquarium can have is the same as the volume of the aquarium:
V=L×W×H=18 in × 8 in × 12 in= 1728 in³
b) The protective covering is used on the four walls of the aquarium. We have to find the areas of the four walls:
One of them is given by the multiplication of the width and the height:
A₁= W×H= 8 in × 12 in=96 in²
The other area is given by the multiplication of the length and the height:
A₂= L×H= 18 in × 12 in= 216 in²
As the fish aquarium is rectangular the area of the walls is given by:
=2×96 in²+2×216 in²=624 in²
We are given the equation:
F = 2.25+0.2(m-1)
where:
F is the fare
m is the number of miles.
In question 7, we are given that the fare (F) is equal to $6.05 and we need to get the number of miles. To do so, we will simply substitute with the fare in the given equation and solve for the number of miles (m) as follows:
F = 2.25 + 0.2(m-1)
6.05 = 2.25 + 0.2(m-1)
6.05-2.25 = 0.2(m-1)
3.8 = 0.2(m-1)
3.8/0.2 = m-1
19 = m-1
m = 19+1
m = 20 miles
Number 8 is exactly the same, but we will substitute F=7.65 and again solve for m
First you graph it using a graphing calculator, you look at the table of values to find out one point in which y= 0. The first one that comes up is when x=1.
If you don't have a graphing calculator you can use trial and error by inputing some numbers into x until you get y= 0.
Once you have an x value which makes y=0, you can start factorizing it.
you divide 6x3 +4x2 -6x - 4 into (x-1) which is when y =0
to get 6x2+10x+4
This can be used to write the polynomial as (x-1)(6x2 +10x+4)
you then factorize the second bracket, 6x2 +10x+4.
you can take the 2 outside to give you 2(3x2 +5x+2)
you can factorize this to become 2(3x+2)(x+1)
Now you just substitute your factorized second bracket into your unfactorized second bracket to give you 2(3x+2)(x+1)(x-1).
From this you can deduce that k= 1
Because angleCBD＋angleBDC＋angleC＝180
so angleCBD＋angleBDC＝180－angleC＝180－82＝98
because BC＝DC
so angleCBD＝angleBDC
so 2 angleCDB＝98
so angleCDB＝49
so y＝29
by Joy Xu，紫馨雪汐
