All categories

2 years ago

F(x)=2x^2-5;find when f(x)=-7

Mathematics

2 answers:

Dominik [7]2 years ago

7 0

Answer:

±i = x

Step-by-step explanation:

f(x)=2x^2-5;

f(x)=-7

-7 = 2x^2 -5

Add 5 to each side

-7+5 = 2x^2 -5+5

-2 =2x^2

Divide by 2

-2/2 =2x^2 /2

-1 = x^2

Take the square root of each side

sqrt(-1) = sqrt(x^2)

±i = x

Daniel [21]2 years ago

6 0

Answer:

x=i or no solution exists depending on the user's grade

Step-by-step explanation:

f(x) = 2x^2-5

-7 = 2x^2-5

-2 = 2x^2, x^2=-1, x=i

You might be interested in

ASAP!! Please help me. I will not accept nonsense answers, but will mark as BRAINLIEST if you answer is correctly with solutions

sp2606 [1]

I believe it is the second one

7 0

2 years ago

A) what is average rate of change of f(x) over the interval from x=5 to x=9? (table shows values of f(x). graph shows function o

SVETLANKA909090 [29]

Answer:

See below for answers and explanations

Step-by-step explanation:

Part A

The average rate of change of a function over the interval $[a,b]$ is equal to $\frac{f(b)-f(a)}{b-a}$ , hence:

$\frac{f(b)-f(a)}{b-a}\\\\\frac{f(9)-f(5)}{9-5}\\\\\frac{14-(-4)}{9-5}\\ \\\frac{14+4}{4}\\ \\\frac{18}{4}\\ \\\frac{9}{2}$

Therefore, the average rate of change of $f(x)$ over the interval $[5,9]$ is $\frac{9}{2}$ .

Part B

Do the same thing as in Part A:

$\frac{f(b)-f(a)}{b-a}\\ \\\frac{f(1)-f(0.25)}{1-0.25}\\ \\\frac{2-5}{0.75}\\ \\\frac{-3}{0.75}\\ \\-4$

Therefore, the average rate of change of $g(x)$ over the interval $[0.25,1]$ is $-4$ .

Part C

To interpret our answer from Part B in terms of the real world it represents, we say that between 0.25 seconds and 1 second, the ball falls at a rate of 4 feet per second (since our average rate of change is negative).

5 0

1 year ago

Find the slope of the line that passes through (4,-5) and (-2,9)

stiks02 [169]

Answer:

C) -7/3

Step-by-step explanation:

m=(y2-y1)/(x2-x1)

m=(9-(-5))/(-2-4)=(9+5)/-6=14/-6

simplify -14/6 to -7/3

4 0

2 years ago

the price of bread went from 1.50 per loaf to 2.50 per loaf in four years. find the rate of change of the price of bread

Talja [164]

Answer:

I think the answer is 1 I really hope this helps

Step-by-step explanation:

3 0

3 years ago

Use one method to find the LCM of the first set of numbers below. Use the other method to find the LCM of the second set. Show W

Nat2105 [25]

Answer:

The least common multiple (LCM) of two or more non-zero whole numbers is the smallest whole number that is divisible by each of those numbers. In other words, the LCM is the smallest number that all of the numbers divide into evenly.

Step-by-step explanation:

The LCM of 13 AND 17 is 221

The LCM of 40 AND 60 is 120

lcm (40; 60) = 120 = 23 × 3 × 5

4 0

3 years ago

F(x)=2x^2-5;find when f(x)=-7​

F(x)=2x^2-5;find when f(x)=-7