Answer:
The last 15 percent of that would be 39
Step-by-step explanation:

Regardless of the sign of

, we have

(never negative). But multiplying by -1 makes it negative.
On the other hand,

which can never be negative for real

.
Answer: 16 square units
Step-by-step explanation:
let the vertex in quadrant I be (x,y)
then the vertex in quadratnt II is (-x,y)
base of the rectangle = 2x
height of the rectangle = y
Area = xy
= x(12 - x²)
= -x³ + 12x
d(area)/dx = 3x² - 12 = 0 for a maximum of area
3x² = 12
x² = 4
x = ±2
y = 12-4 = 8
So, the largest area = 2 x 8 = 16 square units
QUESTION → 
Start by subtracting 3 from both sides to get
.
Now multiply both sides by the reciprocal of 3/2, which is 2/3.
On the left, we have x, and on the right, -3(2/3) is -2.
So we have x = -2.
Answer: 5 branches and 16 birds.
Step-by-step explanation:
If the number of birds is B, and the number of branches is N.
First we have the equation:
B = 3*N + 1
(3 birds per branch + 1 that was flying around)
for the second equation we have:
B = 4*(N - 1)
(4 birds per branch, but one branch had no birds on it, so there are N -1 branches used)
now we can write:
3*N + 1 = 4*(N - 1)
3*N + 1 = 4*N - 4
4 + 1 = 4*N - 3*N
5 = N
So we had 5 branches, now we can replace it in one of the equations and find the number of birds.
B = 3*N + 1 = 3*5 + 1 = 16