Answer:
Step-by-step explanation:
Given
Two sides of triangle of sides 5 ft and 7 ft
and angle between them is increasing at a rate of 0.9 radians per second
let 
is the angle between them thus
Area of triangle when two sides and angle between them is given
Differentiate w.r.t time
at 
Answer:
Step-by-step explanation:
Eliminate answer 4 immediately, because (4)(3) is not 7.
Look at answer 2: 7x + 3x = 10x, which does not match the middle term 12x in the original polynomial. Eliminate answer 2.
Look at answer 1: 1x + 21x = 22x, which does not match the middle term of the original polynomial. Eliminate answer 1.
All quadratics have solutions. Let's apply the quadratic formula to 3x^2 + 12x + 7: Here a = 3, b = 12 and c = 7, so that the discriminant b²-4ac is
12²-4(3)(7), or 144 - 84, or 60. Being positive, this tells us that the given poly has two real, unequal roots:
-12 ± √60 -12 + 2√15 -12 - 2√15
x = ----------------- = ------------------- and x = --------------------
3 3 3
Normally, if c is a root, then x - c is a factor.
If we try this here, however, the resulting factors do not at all match any of your answer choices.
Don't be offended...but please ensure you have copied this problem down correctly.
This is the answer with the correct work.
