請問 21K-64=K

左右對換為置 如 係 + 正要變 負

k 去由右邊本身係 正 去左 左邊 變 負
所以係.

21k -k ( 由正變負) = 64 ( 由本身-64 變左正)

21K-K=64

20K=64

K = 64/20

K = 3.2

21K-64=K
20K=64
64/20=1K
3.2=K
__________________________________________________________
21K-K=20K
21K=21*K
21*K=K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K
K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K-K=20K
20K=K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K
K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K-K=K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K
(+K-K)=0
K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K=K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K+K
形成等式
=>20*K=20*K
eg.A*B-B=(A-1)*B
=A*B-B=A*B-1*B
=A*B-B=A*B-B
等式成

It's because

21K-64=K

21K=K+64

21K-K =64

20K=64

20K/20=64/20

K=3.2

Also, due to the ques. u raised. Here's the answer

21K-K=20

Due to the rules of polynomials, so 21K and -K is like terms. Therefore, They can be done subtraction. Also, -K=-1*K So:

21K-K=20

20K=20

20K/20=20/20

K=1

21K-64=K

=21K-K=64

=20K=64

=64/20

=3.2

K=3.2

21K-64=K
21K-64+64-K=K+64-K
21K-K=64
20K=64
20K/20=64/20
K=3.2

21K-64=K
21K-K =64
20K =64
K =64/20
K =3.2



有幫助嗎?^^

21K-64=K
21K-K=64
20K=64
K=64/20
K=3.2