4. If the determinant delta of a quadratic equation is positive, the equation has two real roots. If the determinant is negative, it has two imaginary roots. In this case, delta=b^2-4ac=(-1)^2-4*1*4=-15. Therefore, this equation has two imaginary roots.
Answer:
yes.
Step-by-step explanation:
Given that D is the mid point of CE ,
So D will bisect CE, it means the length of DE and CD is equal.
=> DE + CD = CE
As DE and CD are equal,
=> DE + DE = CE
=> 2 DE = CE
Putting values from the question,
=> 2( 7x - 1 ) = 10x + 18
=> 14x - 2 = 10x + 18
=> 14x - 10x = 18 + 2
=> 4x = 20
=> x = 20 / 4
=> x = 10 / 2
=> x = 5

Therefore, the value of x is 5
It is just asking how many meters tall are doors usually at. Clearly 30 meters isn't reasonable so just say how tall most doors are in meters.
Well, how long will it take you to drive 135 miles at 55mph?
at 55 mph, you're doing 55 miles every hour, so we can simply get the quotient of 135/55 and that's how many hours it'll take you to drive 135 miles at that speed.

so, it takes you that long, however, from 3:15 to 5:00pm there are only 45mins + 60mins or 1hr and 45 minutes, namely 1¾ hr.
so 2hrs and 27 minutes is much later than 1¾ hr, so, no dice, you can't arrive at 5pm, actually you'll arrive around 5:42pm.