First, we’re going to use this formula:

2nd number - 1st number
————————————— x 100%
1st number

If we plug in the numbers to this equation:

23-20
———- x 100%
20

And subtract 23 to 20, the answer to this equation is:

3
—- x 100% = 15%
20

In this case, the percent of increase is 15%.

3 0

3 years ago

Solve the quadratic equation x2+8x−30=0 by completing the square.

diamong [38]

Answer:

$\bold{x=-4\pm\sqrt{46}}$

Step-by-step explanation:

$(a+b)^2=a^2+2ab+b^2\\\\\\x^2+8x-30=0\\\\\underbrace{x^2+2\cdot x\cdot 4+4^2}-4^2-30=0\\\\{}\qquad(x+4)^2\,-\,16-30=0\\\\{}\qquad\ \ (x+4)^2=46\\\\ {}\qquad\ \ x+4=\pm\sqrt{46}\\\\ {}\qquad\ \ x=-4\pm\sqrt{46}$

5 0

3 years ago

A study has demonstrated that the more television a person watches, the lower that person’s level of physical fitness. However,

Murljashka [212]

Answer: D

Step-by-step explanation:

3 0

3 years ago