1. Using the exponent rule (a^b)·(a^c) = a^(b+c) ...
Simplify. Write in Scientific Notation
2. You know that 256 = 2.56·100 = 2.56·10². After that, we use the same rule for exponents as above.
3. The distributive property is useful for this.
(3x – 1)(5x + 4) = (3x)(5x + 4) – 1(5x + 4)
... = 15x² +12x – 5x –4
... = 15x² +7x -4
4. Look for factors of 8·(-3) = -24 that add to give 2, the x-coefficient.
-24 = -1×24 = -2×12 = -3×8 = -4×6
The last pair of factors adds to give 2. Now we can write
... (8x -4)(8x +6)/8 . . . . . where each of the instances of 8 is an instance of the coefficient of x² in the original expression. Factoring 4 from the first factor and 2 from the second factor gives
... (2x -1)(4x +3) . . . . . the factorization you require
Answer:
Step-by-step explanation:
how we supposed to do it , when we cant control it
Comment
This is an area problem. The key words are 120 square feet and 12 feet longer.
And of course width is a key word when you are reading this.
Formula
Area = L * W
Givens
W = W
L = W + 12
Substitute and Solve
Area = L* W
120 = W*(W + 12)
W^2 + 12W = 120 square feet
w^2 + 12w - 120 = 0
This does not factor easily. I would have thought that a graph might help but not if the dimension has to be to the nearest 1/100 of a foot. The only thing we can do is use the quadratic formula.
a = 1
b = 12
c = - 120
w = [ -b +/- sqrt(b^2 - 4ac) ]/(2a)
w = [-12 +/- sqrt(12^2 - 4*(1)(-120)] / 2*1
w = [-12 +/- sqrt(144 - (-480)]/2
w = [-12 +/- sqrt(624)] / 2
w = [- 12 +/- 24.979992] / 2 The minus root has no meaning whatever.
w = (12.979992) / 2
w = 6.489995 I'll round all this when I get done
L = w + 12
L = 6.489995 + 12
L = 18.489995
check
Area = L * W
Area = 6.489995*18.489995
Area = 119.999935 The difference is a rounding error
Answer
L = 18.489995 = 18.49 feet
W = 6.489995 = 6.49 feet
Note: in the check if you round first to the answer, LW = 120.0001 when you find the area for the check. Kind of strange how that nearest 1/100th makes a difference.
Answer:
a)
b) 334,858 bacteria
c) 4.67 hours
d) 2 hours
Step-by-step explanation:
a) Initial number of bacteria is the coefficient, that is, 250. And the growth rate is the coefficient besides “t”: 0.15. It’s rate of growth because of its positive sign; when it’s negative, it’s taken as rate of decay.
Another way to see that is the following:
Initial number of bacteria is N(0), which implies . And . The process is:
b) After 2 days means . So, we just replace and operate:
c)
d)
Step-by-step explanation:
I don't know if the first set of numbers is all in one set, but I'll do my best to give you an answer.
Really all you need to do is use PEMDAS for the first question.
(Parentheses, exponents, multiply, divide, add, subtract. In that order)
Then to simplify that fraction next to it, notice that 0.018 is 3x 0.06.
that's a 3:1 ratio, so it ends up simplifying to this:
Lastly, to solve the division of that fraction. If you divide by a fraction, you multiply whatever it's dividing by its inverse.
So...