Answer: Hence Pair( x, y) = [ 105/2, 105/2]
Step-by-step explanation:
Given that;
Among all pairs of numbers with a sum of 105;
the pair whose product is maximum = ?
so let pairs of numbers with a sum of 105 be x and y respectively
x + y = 105
let y = 105 - x
now
product = xy = x( 105 - x ) = 105x - x²
now
p(x) = 105x - x²
for maximum value of p
dp/dx =0
⇒ dp/dx = 105 - 2x = 0
2x = 105
x = 105/2
y + x = 105
y = 105 - x
y = 105 - 105/2 = 105/2
Hence Pair( x, y) = [ 105/2, 105/2]
6x + 6 > 3x+ 15
3x > 9
x > 3
Answer:
$409.86
Step-by-step explanation:
To find the price after marking it up, 230 x 0.65 = 149.5
230 + 149.5 = 379.5
Usually we add tax after the discount/markup.
379.5 x 0.08 = 30.36
379.5 + 30.36 = $409.86
Hope this helps!
Answer:
Sydney's age is 28
Step-by-step explanation:
Let Devaughn be D
And Sydney be S
D=S+8..... equation 1
D+S=64...... equation 2
Substitute equation 1 to equation 2
S+8+S=64
2S+8=64
2S=64-8
2S=56
S=56/2
S=28
Hope it helps
Good luck