He made a mistake in step #2. It seemed to be a trivial mistake because it involved signs, but it still had a great impact. Since step#2, his solution was already wrong.
Instead of
(-1)²-4(2)(-6) = 1 + 48 = 49
What he did is
(-1)²-4(2)(-6) = -1 + 48 = 47
Is the answer to your question 9?
Answer:
3,406.5 litres/hr
Step-by-step explanation:
The liquid is being poured at a rate of 15 gallons per minute.
1 minute = 1/60 hour
Thus, the rate can be written as:
15 gallons pet 1/60 hour
We are told that one gallon is approximately 3.785 liters.
Thus;
15 gallons = 15 × 3.785 litres = 56.775 litres.
Thus, the rate is;
56.775 litres per 1/60 hour
We want to find in litres/hr.
By proportion, we have it as;
(56.775 ÷ 1/60)/1 = 56.775 × 60 = 3,406.5 litres/hr
<span>(2.5×10^−10)(7×10^−6)
= (2.5 x 7) (</span>10^−10 x 10^−6)
= 17.5 x 10^-16
= 1.75 x 10^-15
answer
<span>B. 1.75×10^−15 </span>