Answer:
QR = 5
Step-by-step explanation:
Since the parallelograms are similar, then the ratios of corresponding sides are equal, that is
= 
, then
= 
( cross- multiply )
9QR = 45 ( divide both sides by 9 )
QR = 5
The equation for exponential decay is
, where <em>a</em> is the initial amount, <em>b</em> = 1 + <em>r</em> (the growth rate as a decimal number) and <em>x</em> is the number of time periods (in this case, minutes). Substituting the information we have:
. To the nearest tenth of a gram, this would be 1.0 grams.
Answer:
Step-by-step explanation:
We have the equations
4x + 3y = 18 where x = the side of the square and y = the side of the triangle
For the areas:
A = x^2 + √3y/2* y/2
A = x^2 + √3y^2/4
From the first equation x = (18 - 3y)/4
So substituting in the area equation:
A = [ (18 - 3y)/4]^2 + √3y^2/4
A = (18 - 3y)^2 / 16 + √3y^2/4
Now for maximum / minimum area the derivative = 0 so we have
A' = 1/16 * 2(18 - 3y) * -3 + 1/4 * 2√3 y = 0
-3/8 (18 - 3y) + √3 y /2 = 0
-27/4 + 9y/8 + √3y /2 = 0
-54 + 9y + 4√3y = 0
y = 54 / 15.93
= 3.39 metres
So x = (18-3(3.39) / 4 = 1.96.
This is a minimum value for x.
So the total length of wire the square for minimum total area is 4 * 1.96
= 7.84 m
There is no maximum area as the equation for the total area is a quadratic with a positive leading coefficient.
Answer:
J's would be (-5,-4) if J was reflected over the line x=3.
