1.given that 4:(y+7)=7:(3y+16),find y
2.given that (y+4):y=5:6,find y
3. the ratio of the interior angles of a triangle is 4:2:3,find the smallest angle.
(you can only answer one question)
maths:about rate&ratio(贈送20點)
2008-03-28 3:52 am
回答 (3)
2008-03-28 4:04 am
✔ 最佳答案
The question 17(y+7)=4(3y+16)
7y+49=12y+64
5y=-15
y= -3
2008-03-28 4:12 am
1. 4:(y+7) = 7:(3y+16)
4/(y+7) = 7/(3y+16)
(y+7)(3y+16) = 7(4)
4y+7+16 = 28
4y+23 = 28
4y = 28-5
4y = 5
y = 5/4
y =1.25
2. (y+4):y = 5:6
(y+4)/y = 5/6
6(y+4) = 5y
6y+24 =5y
24 = 5y-6y
24 =-y
y = -24
3. The smallest angle
= 180。x 2/4+2+3
= 180。x 2/9
= 40。
4/(y+7) = 7/(3y+16)
(y+7)(3y+16) = 7(4)
4y+7+16 = 28
4y+23 = 28
4y = 28-5
4y = 5
y = 5/4
y =1.25
2. (y+4):y = 5:6
(y+4)/y = 5/6
6(y+4) = 5y
6y+24 =5y
24 = 5y-6y
24 =-y
y = -24
3. The smallest angle
= 180。x 2/4+2+3
= 180。x 2/9
= 40。
2008-03-28 4:05 am
1.given that 4:(y+7)=7:(3y+16),find y
4/(y+7)=7/(3y+16)
12y+64=7y+49
5y=--15
y=-3
2.given that (y+4):y=5:6,find y
(y+4)/y=5/6
6y+24=5y
y=-24
3. the ratio of the interior angles of a triangle is 4:2:3,find the smallest angle.
2/(4+2+3)x360°
=2/9x360°
=80°
4/(y+7)=7/(3y+16)
12y+64=7y+49
5y=--15
y=-3
2.given that (y+4):y=5:6,find y
(y+4)/y=5/6
6y+24=5y
y=-24
3. the ratio of the interior angles of a triangle is 4:2:3,find the smallest angle.
2/(4+2+3)x360°
=2/9x360°
=80°
收錄日期: 2021-04-29 16:20:47
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