Answer:
D=-4<0, the equation has no real solutions, it has two imaginary solutions.
Step-by-step explanation:
The quadratic equation
has coefficients
a=1,
b=4,
c=5.
The discriminant D is the expression

Hence,

Since the discriminant is negative, the equation has no real solutions, it has two imaginary solutions.
Answer:
Press A takes 10 hours to do a certain job. So Press A does (1/10)th of the job in an hour.
Press A and Press B, together do (1/2.5) or (4/10)th of the job in an hour.
So Press B does (4/10)-(1/10) = (3/10)th of the job in an hour. So Press B can do the job in (10/3) hours or 3 hour and 20 mins.
Check: A does (1/10)th and B does (3/10)th part of the job in an hour. A and B together will take (1/10)+(3/10) = 4/10th of the job in an hour. So they will complete the job in 10/4 = 2.5 hours. Correct.
Answer: Press B can do the job in 3 hour and 20 mins.
Step-by-step explanation:
Answer:
A. 3 bags of oranges, 4 bags of apples
Step-by-step explanation:
If O is number of bags of oranges and A is number of bags of apples:
O + A = 7
5O + 3A = 27
We can solve this system of equations with either substitution or elimination. I like to use substitution, but you can use whichever you prefer.
O = 7 − A
5 (7 − A) + 3A = 27
35 − 5A + 3A = 27
35 − 2A = 27
8 = 2A
A = 4
O = 7 − A
O = 3
Teresa bought 3 bags of oranges and 4 bags of apples.
In this case, since one equation is in the form of x=, substitution would be best for this problem. Simply plug in 4y + 8 in place of x in the second equation, solve for y, then plug that value into the first equation to find x.