When a photograph is taken, the exposure time, t is directly proportional to the square of the size, f , of the opening in the camera lens. t = 0.02 when f = 8. it can be shown that t = 1/3200 f squared. calculate the value of f when t = 0.0098

f = 5.6

Step-by-step explanation:

given the quantities are proportional then the equation relating them is

t = kf² ← k is the constant of proportionality

To find k use the condition t = 0.02 when f = 8

k = = =

t = ← equation of proportionality

when t = 0.0098, then

0.0098 = ( multiply both sides by 3200 )

f² = 0.0098 × 3200 ( take the square root of both sides )

f = = 5.6

by definition, an arc subtended by a central angle of some given measure has the same measure. so .

(2x + 16) + (x) = 180

step-by-step explanation:

given,

abcd is a quadrilateral inscribed in a circle

angle a is labeled x plus 16, (x + 16)

angle b is labeled x degrees, (x)

angle c is labeled 6x minus 4, (6x – 4)

angle d is labeled 2x plus 16, (2x + 16)

what equation can be used to solve for angle b?

we know that the sum of the opposite angles of a simple quadrilateral inscribed in a circle is 180 degrees.

angle b is opposite angle d

therefore, angle b + angle d = 180

(x) + (2x + 16) = 180 

same as (2x + 16) + (x) = 180