F(-4)= -4(-4) -2
F(-4)= 14
A. 7 + 3 x (2 + 4) = 25
7 + 3 x 6 = 25
7 + 18 = 25
25 = 25
B. 8^2 divided by 4 x 8 = 2
64 divided by 4 x 8 = 2
64/32 = 2
2 = 2
C. (16 + 8) - 5 x 2 = 14
24 - 5 x 2 = 14
24 - 10 = 14
14 = 14
For each problem use the basis of the acronym PEMDAS.
P arentheses (grouping symbols)
E xponents
M ultiplication
D ivision
A ddition
S ubtraction
Evaluate each step in that order.
For the first, simply plug in the value of x given (x = 2) into the equation: 
So, 8 would be your answer.
For the second, the sum of x and 2 would be expressed as x + 2. Twice this sum would be written as 2(x+2). Finally, 8 less than twice that sum would be written as 2(x+2) - 8, which would be your expression.
For the last question, the coefficient refers to the number directly in front of the variable, x. So you need only to check what the x would simplify to in each equation and look for the expression where x has no coefficient (i.e., its coefficient is 1). For Hunter, the coefficient would be 15 (5 × 3x = 15x); for Michael, the coefficient would be 11 (6x + 5x = 11x); for Nate, the coefficient would be 1 (x = 1x); and for Spencer, the coefficient would be 2 (2x = 2x). Thus, Nate's expression has a coefficient of 1 when simplified.
Area of a circle is directly proportional to the square of radius of the circle while the circumference is proportional to the radius of the circle. This means that if the radius of a circle is increased x times, then its area will be increased to x^2 times the original area, and the circumference will increase to x times the original circumference.
Thus when the radius is doubled, or in other words if radius mad 2 time the original radius, the area of circle will become 2^2 = 4 time the original area. The circumference will become 2 times the original circumference.
We can calculate exact area and circumference of a circle from its radius using the following equations:
Area of circle = (pi/4)*r^2
Circumference of circle = 2*pi*r
Where r is the radius of the circle.
I know this is a lot, sorry.
