Vì tam giác ABC cân tại A (gt) mà AM là đg trung tuyến nên AM đồng thời là đg cao của t/giác đó:
AM là trung tuyến của t/giác ABC nên M là trung điểm BC:
=> BM =BC/2 =6:2=3(cm)
Xét tam giác AMB vuông tại M
AB^2 =AM^2+BM^2 ( theo định lý Py-ta -go)
Answer:
108 degrees.
Step-by-step explanation:
2x + 16 = 3x - 12 (corresponding angles; AB parallel to CD).
16 + 12 = 3x - 2x
x = 28.
So the angle marked 3x - 12 = 3(28) - 12
= 72 degrees.
Angle y is adjacent to the angle so
y = 180 - 72
= 108 degrees.
Answer:
x = 51
Step-by-step explanation:
(x-3) /4 = 12
Multiply each side by 4
(x-3) /4 *4 = 12*4
x-3 = 48
Add 3 to each side
x-3+3 = 48+3
x = 51
irrational number, any real number that cannot be expressed as the quotient of two integers.
Any number that can be written as a fraction with integers is called a rational number . For example, 17 and −34 are rational numbers. (Note that there is more than one way to write the same rational number as a ratio of integers.
1st Is rational
2nd one is irrational
3rd is irrational
4th is rational
65:100 because there are 65 girls and then 65 girls + 35 boys = 100 total students