Roots test tells us to take the factors of the 20 divided by the factors of the coefficient of the the first.

factors of 20 are 1,2,4,5,10,20
factors of 1 are 1

so plus or minus 1/1, 2/1, 4/1, 5/1, 10/1, 20/1 are all possible rational zeros

8 0

3 years ago

Screenshot with answers included A circle has a radius of 1 cm.

lora16 [44]

Area = $\pi r^{2}$
area = $\pi$ x 1 x 1 = $\pi$

Circumference = $2\pi r$
Circumference = 2 x $\pi$ x1
Circumference = 2 $\pi$

The circumference is greater than the area

6 0

3 years ago

<img src="https://tex.z-dn.net/?f=%20%5Csqrt%7B2x%7D%20%2B%2012%20%3D%20x%20%2B%208%20" id="TexFormula1" title=" \sqrt{2x} + 12

Helga [31]

First note that $x\ge0$ ; otherwise $\sqrt{2x}$ is undefined as long as we're only looking for real solutions.

We can write

$\sqrt{2x}+12=x+8$
$\sqrt{2x}=x-4$
$2x=(x-4)^2$
$2x=x^2-8x+16$
$x^2-10x+16=0$
$(x-8)(x-2)=0$

$\implies x=8,x=2$

4 0

2 years ago