Answer:
70/45
Step-by-step explanation:
(-10/9) divided by (-5/7) = (-10/9) / (-5/7)
dividing two fractions is the same as multiplying the top fraction by the reciprocal of the bottom one
top fraction = -10/9
bottom fraction = -5/7
reciprocal just means switching the numerator and denominator
reciprocal of bottom fraction = 7 / -5 = -7/5
thus,
(-10/9) / (-5/7) = (-10/9) * reciprocal of (-5/7) = (-10/9) * (-7/5) = 70/45
note that to multiply two fractions, you just multiply the numerators to get your new numerator and do the same thing with the denominators
Answer:
32
Step-by-step explanation:
Substitute x = 6 into f(x), that is
f(6) = 6² - 4 = 36 - 4 = 32
I believe the answer would be D.
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.