The square root of 5 less than twice a number is 7. Find the number.

Mathematics

1 answer:

densk [106]2 years ago

3 0

Answer:

4.618

Step-by-step explanation:

Let's use x to represent the number so we can write an equation to solve it.

'twice the number' is represented by 2x so we have our equation:

2x-5^0.5=7

(5^0.5 is just square root 5 because I can't do a square root symbol.)

Now we need to isolate the x term so:

2x-5^0.5+5^0.5=7+5^0.5

2x=7+5^0.5

Square root 5 = 2.236 (3dp)

2x=7+2.236

2x=9.236

2x/2=9.236/2

x=4.618

Hope this helped!

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Write the equation of a piecewise function with a jump discontinuity at x =3. Then, determine which step of the 3-step test for

seraphim [82]

Answer:

Here's a possible example:

Step-by-step explanation:

$f(x) =\begin{cases} x & \quad x < 3\\x+3 & \quad x \geq 3\\\end{cases}$

Each piece is linear, so the pieces are continuous by themselves.

We need consider only the point at which the pieces meet (x = 3).

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