Answer:
0.9
Step-by-step explanation:
Answer:
r = 9
Step-by-step explanation:
Given that c varies directly as (r + 1) then the equation relating them is
c = k(r + 1) ← k is the constant of variation
To find k use the condition c = 8 when r = 3, then
8 = k(3 + 1) = 4k ( divide both sides by 4 )
2 = k
c = 2(r + 1) ← equation of variation
When c = 20, then
20 = 2(r + 1) ← divide both sides by 2
10 = r + 1 ( subtract 1 from both sides )
9 = r
The television set has a rectangular shape. The diagonal of this rectangle along with its width and length together form a right angular triangle.
This means that we can apply the Pythagorean theorem which states that:
(diagonal)^2 = (length)^2 + (width)^2
Let the width be w. We know that the length is 0.75 times the width, this means that: length = 0.75 w
Substitute in the above equation:
(20)^2 = (0.75w)^2 + (w)^2
400 = 0.5625 w^2 + w^2
400 = 1.5625 w^2
w^2 = 256
w = 16
This means that the width of the screen is 16 in.