<em>Correct expression: </em>
Answer:
x = 4
x = -4
x = 7i or 
x = -7i or 
Step-by-step explanation:
We do factorization of x^2 - 16
(x^2-16) = (x+4)(x-4)
(x+4)(x-4)(x^2+49) = 0
We require that any term in the multiplication to be zero to fulfil the requirement
so:
if x + 4 = 0 then (x+4)(x-4)(x^2+49) = 0
x = -4
if x - 4 = 0 then (x+4)(x-4)(x^2+49) = 0
x = 4
if (x^2+49) = 0 then (x+4)(x-4)(x^2+49) = 0
x^2 = -49
we have two roots:
If your course has already worked with complex number and the root of -1 then:
7i and -7i are solution as well
because 7i will be: 
and the same reasoning for -7i: 
Answer:
B.(-6,-1)
Step-by-step explanation:
Answer: d) 3 hours.
Step-by-step explanation:
Let x be the required number of hours for which the total fee charged by the companies the same.
Given: Peppy Pets charges a flat fee of $15 plus $3 per hour .
So Total charge = 15+3x ( in dollars)
Happy Hounds charges a flat fee of $21 plus $1 per hour.
So Total charge = 21+x ( in dollars)
When the total charge for both companies are the same, then
Hence, the correct option is d) 3 hours.
Answer:
( 0 < y < 23 / 6 ) mins
Step-by-step explanation:
Solution:-
We will define a variable ( x ) as the time it took for Jo Anne to give her speech at home.
The time taken to give her speech must always be less than 4 minutes. We can express this mathematically using an inequality as follows:
( 0 < x < 4 ) minutes
Jo Anne gave her speech which was 10 seconds less than the one she practised at home. We will convert the time in seconds to minutes as follows:
The time taken by Jo Anne to complete her speech in English class can be represented as:
y = x - 1/6
Using the range of time that Jo Anne could take in delivering her speech in the class would be:
0 < x < 4
0 - 1/6 < y < 4 - 1/6
-1/6 < y < 23 / 6
Since time can not be less than zero. We correct the lower limit to " 0 " as follows:
( 0 < y < 23 / 6 ) mins
Answer:
4
Step-by-step explanation:
Solving for h(t) = 0, we find ...
0 = -16t^2 +256
0 = -t^2 +16 . . . . . . divide by 16
t^2 = 16 . . . . . . . . . .add t^2
t = 4 . . . . . . . . . . . . .positive square root
The ball hits the ground after 4 seconds.
