Answer:

where
is the number of laptops, and
is the year.
in 2017: 
Step-by-step explanation:
I will define the variable
as the number of years that passed since 2007.
Since the school buys 20 lapts each year, after a number
of years, the school will have
more laptops.
and thus, since the school starts with 31 laptops, the equation to model this situation is

where
is the number of laptops.
since x is the number of years that have passed since 2007, it can be represented like this:

where
can be any year, so the equation to model the situation using the year:

and this way we can find the number of laptos at the end of 2017:

and


Answer:
Step-by-step explanation:
1) ABCD is a trapezium. AB ║ CD
∠ADC + ∠DAB = 180° { Co interior angles}
110° + ∠DAB = 180
∠DAB = 180 -110
∠DAB = 70°
2) Sum of all angles of trapezium = 360°
∠A + ∠B + ∠DCB + ∠D = 360
70° + 50° + ∠DCB + 110° = 360
230 + ∠DCB = 360
∠DCB = 360 - 230
∠DCB = 130°
3) For finding the height, use Pythagorean theorem
height² + base² = hypotenuse²
height² + 6² = 10²
height² + 36 =100
height² = 100 - 36
height² = 64
height = √64
height = 8 m
4) a = AB = x m
b = 9 m
h = height = 8 m
Area of trapezium = 120 m²
= 120

x + 9 = 120/4
x + 9 = 30
x = 30 - 9
x = 21 m
AB = 21m
The area of the mirror (v) is 9.5x7.5=71.25 inches
A radius of a circle or sphere is any of the line segments from its center to its perimeter, and in more modern usage, it is also their length. Set up the formula for the area of a circle. The formula is A = π r 2 it equals the area of the circle, and r equals the radius.
Solve for the radius.
Plug the area into the formula.
Divide the area by.
Take the square root.
Let x + 1.5 be length of segment above left hand
Let 2x be length of segment below left hand
15 = x + 1.5 + 2x
15 = 3x + 1.5
15 - 1.5 = 3x
13.5 = 3x
13.5/3= 3x/3
4.5 = x
x = 4.5
This is the length above the left hand.
2x must be then 4.5*2 = 9 foot
This is the length below the left hand.
Checking
4.5 + 9 + 1.5 = 15 foot
Adding length below left hand & length of left hand to right hand:
9 + 1.5 = 10.5
The right hand is hence 10.5 foot far up the pole.