A có // với b không? Vì sao
<style id="sweezy-cursors--styles" type="text/css">body a,
body button,
body [type='button'],
body input[type='reset'],
body input[type='submit'],
body [role="button"],
::-webkit-search-cancel-button,
::-webkit-search-decoration,
::-webkit-scrollbar-button,
::-webkit-file-upload-button,
body .sweezy-custom-cursor-hover {
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}</style>
----- Nội dung dịch tự động từ ảnh -----
Bài 4 (3đ):
Cho hình vẽ bên, biết ZB,= 75°, alc,blc
a) a có song song với b không? vì sao?
b) Tính ZA,
c) Tính ZA,
a
750
B.
b.
Bài 5(1đ): Cho a, b, c là các số khác 0 sao cho :
a+b-c a-b+c -a+b+c
b
a
Tính giá trị biểu thức: M=
(a +b)(b+c(c +a)
abc
1 trả lời
91