The sale price is $30.52
:)
Answer:
Step-by-step explanation:
Let he speed of the boat on the lake is x.
<u>Considering the speed of the current it will take him:</u>
- 22.5/(x + 6) + 22.5/(x - 6) = 9
- 2.5 / (x + 6) + 2.5 / (x - 6) = 1
- 2.5(x - 6 + x + 6) = (x + 6)(x - 6)
- 2.5*2x = x² - 36
- x² - 5x - 36 = 0
- x = (5 ± √(5² + 4*36))/2 = (5 ± 13) / 2
- x = (5 + 13)/2 = 9 mph (negative root is discarded as the speed should be positive)
<span>X^3+6x^2-17x+2-x^3-x^2-11x+36 = </span>5x^2 - 28x + 38
Answer:12
Step-by-step explanation:
Let the numbers be a and b
a-3b=5 ........equation (1)
There product is :
ab=68 ..........equation (2)
From equation (1)
a-3b=5
Make a the subject of the formula
a=5+3b. ........equation (3)
Substitute equation (3) into equation (2)
(5+3b)b=68
3(b^2)+3b-68=0
The product is -204b^2(17 and -12)
(b+17)(b-12)=0
b=-17 or b=12
So the number is 12
