Answer: 39.2 minutes
Step-by-step explanation:
Angela used 56minutes. Brain used 70% of Angela's time which will be 70% of 56.
70/100 × 56 = 39.2 minutes.
Therefore, Brian used 39.2 minutes for the test.
The answer is the answer is C and F.
This is found by inserting the equation above into the quadratic formula or -b plus or minus the square root of b^2 - 4ac over 2a.
With that, you find that the first number is a -3, which eliminates choices B and D.
Then, solving the 4ac portion, you find that inside the square root the number is 29, which gives you the last two answer choices.
Hope this helps!
Answer:
The function (gof)(x) is;

Explanation:
Given the functions;

Solving for the function;

so, we have;

Therefore, the function (gof)(x) is;

x − y = 0 = difference
x + y = 4 = sum
Can be solved by the sum and difference rule (most of the time without pen and paper)
x=(sum+difference)/2=0+4/2=2
y=(sum-difference)/2=(4-0)/2=2