It's the graphs that don't touch the x-axis have complex roots. Roots are the points where the parabola touches the x-axis. A,C and E all cross/touch the x-axis so they have real roots.
In the deck of cards, there is a total of 52 cards which
comprises of: kings, queens, jacks, 10, 9, 8, 7, 6, 5, 4, 3, 2, and aces.
In the problem, we were asked the probability of less than
5, so it would be Ace, 2, 3, and 4. 5 is not included since the problem didn’t
ask less than or equal to.
So 4 cards and we have 4 suits in the deck. So 4 x 4 = 16.
The length of a table, the width of a classroom, and the length of a car can be easily measured without using trigonometry (could probably use a meter stick or measuring tape) because we can easily reach both ends
the width of a wide river is a little different, it may not be practical to measure the distance across directly.
