All categories

2 years ago

Simplify (7x + 2 + 8x

1 answer:

6 0

(7x + 2 + 8x^4) – (2x – 5 – 8x^4) + (3x + 5x^4)
= 7x + 2 + 8x^4 – 2x + 5 + 8x^4 + 3x + 5x^4
= 8x + 7 + 21x^4
= 21x^4 + 8x + 7

You might be interested in

You and Mr. Fowles have decided to race each other at the Boston Marathon (26 miles long). Mr. Fowles runs at a steady 4.2 miles

Maslowich

Answer:

The answer is below

Step-by-step explanation:

Speed is the time rate of change of velocity, it is the ratio of distance to time.

Mr. Fowles runs at a steady 4.2 miles per hour. The time taken to cover 26 miles is:

speed = distance / time

time = distance / speed = 26 / 4.2 = 6.19 hour

I run at 3 miles per hour. I was given 3 mile lead, so the remaining distance is 23 miles (26 - 3). The time needed to complete the 23 miles is:

time = distance / speed = 23 / 3 = 7.67 hour

a) Let d be the distance Mr Fowles catches me. Hence:

time = (d + 3)/4.2; also time = d/3

(d + 3)/4.2 = d/3

3d + 9 = 4.2d

1.2d = 9

d = 7.5 miles

He would catch me at 10.5 (7.5 + 3) miles from the starting point.

b) Mr. fowles finishes after 6.19 hour. At that time, the distance is have covered is:

distance = 6.19 * 3 mi/hr = 18.57 mile

Distance behind = 23 mile - 18.57 = 4.43 mile

c) time longer = 7.67 hour - 6.19 hour = 1.48 hour

4 0

2 years ago

A cab company charges $0.80 per mile plus $2 for tolls. Melissa has at most $16 to spend on her cab fare. Write and solve an ine

Anna35 [415]

Answer:

The maximum distance is 17.5 miles

No she can't make to the airport.

Step-by-step explanation:

Given the cab charges $0.8 per mile and $2 for tolls.

let the miles travelled by melissa be x.

The total charge is $ $(0.8*x+2)$

Now given that she can spend a maximum of $16

so the inequality is

$0.8*x+2\leq 16$

$0.8*x\leq 14$

$x\leq \frac{14}{0.8}$

$x\leq 17.5$

Therefore the maximum distance she can travel is 17.5 miles

Since the distance to airport is 25 miles which is greater than 17.5 miles she cannot afford the cab.

3 0

3 years ago

A line tangent to the curve f(x)=1/(2^2x) at the point (a, f(a)) has a slope of -1. What is the x-intercept of this tangent?

kirza4 [7]

Answer:

x-intercept = 0.956

Step-by-step explanation:

You have the function f(x) given by:

$f(x)=\frac{1}{2^{2x}}$ (1)

Furthermore you have that at the point (a,f(a)) the tangent line to that point has a slope of -1.

You first derivative the function f(x):

$\frac{df}{dx}=\frac{d}{dx}[\frac{1}{2^{2x}}]$ (2)

To solve this derivative you use the following derivative formula:

$\frac{d}{dx}b^u=b^ulnb\frac{du}{dx}$

For the derivative in (2) you have that b=2 and u=2x. You use the last expression in (2) and you obtain:

$\frac{d}{dx}[2^{-2x}]=2^{-2x}(ln2)(-2)$

You equal the last result to the value of the slope of the tangent line, because the derivative of a function is also its slope.

$-2(ln2)2^{-2x}=-1$

Next, from the last equation you can calculate the value of "a", by doing x=a. Furhtermore, by applying properties of logarithms you obtain:

$-2(ln2)2^{-2a}=-1 \\\\2^{2a}=2(ln2)=1.386\\\\log_22^{2a}=log_2(1.386)\\\\2a=\frac{log(1.386)}{log(2)}\\\\a=0.235$

With this value you calculate f(a):

$f(a)=\frac{1}{2^{2(0.235)}}=0.721$

Next, you use the general equation of line:

$y-y_o=m(x-x_o)$

for xo = a = 0.235 and yo = f(a) = 0.721:

$y-0.721=(-1)(x-0.235)\\\\y=-x+0.956$

The last is the equation of the tangent line at the point (a,f(a)).

Finally, to find the x-intercept you equal the function y to zero and calculate x:

$0=-x+0.956\\\\x=0.956$

hence, the x-intercept of the tangent line is 0.956

5 0

2 years ago

To the nearest tenth of a mile how many miles from the runway is the airplane at the start of this approach the figure is not dr

nikklg [1K]

Hey guys im gonna be really nice, ima give you the answers for connexus <span>Geometry Semester B: 1) D 2) B 3) A 4) D 5) B 6) C 7) D 8) A 9) A 10) NO 11) OBTUSE 12) C 13) A 14) D 15) B 16) A 17) LAST GRAPH 18) D 19) A 20) B 21) B 22) B 23) C 24) A 25) B 26) A 27) A 28) B 29) B 30) B 31) A 32) A 33) B 34) B 35) B 36) D 37) A 38) A 39) A 40) B 41) D 42) A 43) B 44) A 45) B 46) D 47) C 48) A 49) D 50) D
These r 100% correct i promise if ur in connexus you will get all correct! hope this helps you guys out :3</span>

4 0

3 years ago

8-1 1/5<br> (Simplify your answer. Type a whole number, fraction, or a mixed number.)<br> orrect:

ozzi

The answer is 6 4/5!

6 0

3 years ago

Read 2 more answers