Answer:
Hans has done a mistake in the second step.
The correct answer is:
5x^2+13x-6=0
5x^2+15x-2x-6x=0 - 5. -6=-30 -30=15. -2
5x(1+3x)-2x(1+3x)=0
(5x-2x)(1+3x)=0
5-2x=0 1+3x=0
x=5/2 x=-1/3
(1/12)X = 6800
6800/ (1/12) = X
X = 81600 (hours)
6800 (6.8 * 10^3) divided by 1/12 (12^-1) equals 81600. It will take 81600 hours for the pool to completely empty at a rate of 0.833333333 or 12^-1 gallons per second.
Answer:
85
Step-by-step explanation:
10x13=130, 9x5=45, 130-45=85
Answer:
y = 15x + 20
Step-by-step explanation:
He charges a flat rate of $20, so any total for hours worked will have an additional $20 added to it.
The 15x represents his earnings per hour. He makes 15 per every hour worked, x represents the number of hours worked