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
Answer:
The train going 30 miles in 1/3 hour is going faster than the other train.
Step-by-step explanation:
Calculate each rate by dividing the distance traveled by the amount of time it takes to cover that distance:
30 / (1/3) = 90 mph
20 / (1/2) = 40 mph
~(-19,32)
Equation form x=-19,y=32
