X - 48 = 19 + 18
X = 37 + 48
X = 85
Hai số đó là 90 và 10
Hiệu ⇒ 90 - 10 ⇒ 80
⇒ Hiệu = 80
Đáp án: X= 85
Số tròn chục lớn nhất có 2 chữ số là số 90, số tròn chục bé nhất có 2 chữ số là 10. Hiệu của 2 số đó là 80
Giải thích các bước giải:
vì
X-48=19+18
X-48=37
X=37+48
X= 85
Vì sao vào những ngày trời nóng, hanh khô thì ko nên lau màn hình vi tính, ti vi mà chỉ nên dùng chổi lông quét nhẹ thôi.
Giúp em bài số 6,7,8, đi ạ em cảm ơn ❤️❤️
Làm giúp mình câu này với ạ Cho biểu thức A = 17 + (x - y) - (10 - y - x) a) Rút gọn biểu thức A b) Tính giá trị biểu thức A, biết x = 12 ; y = 21
cho tam giác ABC cân tại a (góc a<90°).Kẻ BD vuông góc AC (D€AC), kẻ CE vuông góc AB (E€AB). chứng minh rằng AD=AE b,gọi I là Giao điểm của BD và CE.CHỨNG minh AI là tia phân giác góc A c, tính độ dài BC, biết AD=7cm DC=1cm
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