20^2=400

So the root number is 400=20. Similarly, the root number is 169= 13.

So =0. 1*20+0.2* 13.

=2+2.6

=4.6

Root number 484- root number 12 and 1/4+ root number 20.25

484 = 22 2, 12 and one quarter = 49/4 = (7/2) 2,20.25 = 4.52.

so = 22-7/2+4.5 = 22-(3.5-4.5)= 22- 1 = 2 1。

Find the value of x suitable for the following types.

The square of x -36 =0

x^2=36=( 6)2

x= 6

25X squared =64

x^2=64/25=( 8/5)^2

x= 8/5

The square of (X-2) = 196

(x-2)^2=( 14)^2

x-2= 14

x=2 14

x 1=2+ 14= 16，x2=2- 14=- 12

The square of (2X+ 1) = the square of (-3)

(2x+ 1)^2=(-3)^2=9=( 3)^2

2x+ 1= 3

2x=- 1 3

x =(- 1 ^ 3)/2

x 1 =(- 1+3)/2 = 1 . x2 =(- 1-3)/2 =-2

Seeking cubic root

Cubic root number 3 and 3/8+ cube root number 0. 125

3 3/8 = 27/8 = (3/2) 3

0. 125=0.5^3

So =3/2+0.5

=2

Cubic radical 5- 27 times 10(-3+2 and 7/8)

Because two and seven eighths =23/8.

So in the third root number = 5- 10 *(3+23/8)/27.

=5- 10(- 1/8)/27

=5+ 10/2 16

= 1090/2 16

= 1090/(6^3)

So the original formula = (cube root number 1090)/6.

Find x

X^3+ 1=37/64

x^3=37/64- 1=-27/64=(-3/4)^3

x=-3/4

27(X- 1)^3+ 125=0

(x- 1)^3=- 125/27=(-5/3)^3

x- 1=-5/3

x=-5/3+ 1=-2/3