The formula for the light bend would be n1*sin i= n2 * sin r
If you use "sin (90-x)= cos x" principle, you can change the sin in the equation into
n1*sin i= n2 * sin r
n1 * cos a= n2 * cos b
n2/n1= cos a/ cos b
Assuming the n constant is the ratio of the glass compared to water then the answer would be: cos a/ cos b
The answer is no i do not agree
Bob need to paint 205 square feet.
Solution:
Length of the door = 7 ft
Breadth of the door = 5 ft
Area of the door = length × breadth
= 7 × 5
= 35
Area of the door = 35 ft²
The given image is a trapezoid.
Top base = 12 ft
Bottom base = 20 ft
Area of the trapezoid = 


= 240
Area of the trapezoid = 240 ft²
Surface area to paint = Area of the trapezoid – Area of the door
= 240 ft² – 35 ft²
= 205 ft²
Hence Bob need to paint 205 square feet.
Answer:
Step-by-step explanation:
2x(x - 3) + 7(x - 3)
2x^2 - 6x + 7x - 21
reduce
2x^2 + x - 21
if this is equal to 0 then:
2x^2 + x - 21 = 0
factored:
(2x + 7)(x - 3) = 0
How that was done:
Divide the (2x^2) into (2x) and (x).
Divide the (-21) into (+7) and (-3). You choose these numbers so that their sum, when multiplied by (2x) and (-3), adds up to (+x).
So umm ahh I won't tell answer but I'll teach <u>HOW</u> to solve it :>
Sooo........
Just ask your teacher that is the best best best helpful hint (IT IS ACTUALLY)