Answer:
D
Step-by-step explanation:
This questions asks use to find what f(x) or y is, when x is equal to -2.
So, substitute -2 in for x in the equation.
f(x)=2(4)^x
f(-2)=2(4)^-2
Evaluate the exponent. Negative exponents follow this rule:
b^-x= 1/b^x
We have 4^-2. This will become 1/4^2 or 1/16
f(-2)=2(1/16)
Multiply
f(-2)=2/16
This fraction can be simplified. Both the numerator (top number) and denominator (bottom number) can be divided by 2.
f(-2)=2/2 / 16/2
f(-2)= 1/8
The correct choice is D. 1/8
Answer:
Option C. 4(20-16y): Each side measures 20-16y units.
Step-by-step explanation:
we know that
The perimeter of a square is equal to

where
b is the length side of the square
we have

substitute the given value in the formula

solve for b
Divide by 4 both sides

Rewrite the expression

<em>Alternative Method</em>
we have

Factor 4

so
Each side measures (20-16y) units.
7.380 times 10 to the 9th power (or 7.38 times 10 to the 9th power)
We have, /x+5.3/ = 2.1;
Then, x + 5.3 = 2.1 or x + 5.3 = -2.1;
x = 2.1 - 5.3; x = -3.2;
x = -2.1-5.3; x = -7.4;
The correct answer is c.