Answer:
The length is 7 m
The width is 10 m
Step-by-step explanation:
length = x
width = 2x - 4
length * width = area
It is given that the area is 70 
From there
x * (2x - 4) = 70
- 4x = 70
- 4x - 70 = 0
- 2x - 35 = 0
Now we have a quadratic equation, which is a + bx + c = 0, where a 
0
In this equation a = 1, b = -2 and c = -35
Discriminant (D) formula is b² - 4ac
D = 
- 4 * 1 * (-35) = 144 > 0
This discriminant is more than 0, so there are two possible x
Their formulas are 
and 
= 
= -5 < 0 (the length of the rectangle has to be more than 0, so we don't use this x)
= 
= 7 > 0 (this one is right)
Calculating the dimensions
length = x = 7 (m)
width = 2x - 4 = 2 * 7 - 4 = 10 (m)
Answer:
1.20
Step-by-step explanation:
Let mean be represented by M and standard deviation by d. The score will be x and sample number of games be n
To get the test statistic, t for Fernanda's test, we use the formula
Substituting 156 for mean, M then 150 for score x and 30 for standard deviation while 36 for n then
t=1.20 when put in two decimal place
We have two points on a plane p1(150, 25000), p2(90, 19000) and we can find a linear equation from them, lets calculate the slope:
m = (y2 - y1)/(x2 - x1)
where x1, y1 and x2, y2 are the point's coordinates:
m = (19000 - 25000)/(90 - 150)
m = -6000/-60
m = 100
so we have the slope now, and we can use the equation of the line for a point and having the slope, that equation is:
y - y1 = m(x - x1)
so we substitute:
y - 25000 = 100(x - 150)
y = 100x + 25000 - 15000
y = 100x + 10000
so this is the linear equation that models the airplane descent, when the airplane hits the ground, then y = 0, and we need to find the x, that is the position in relation to the runway:
<span>0 = 100x + 10000
</span>-100x = 10000
x = -100
