有幾條數學題唔識做牙

1.Make y the subject of the formula ay=k=123
ay=k=123
ay=k ay=123
y=a分之之k y=a分之123

2.Make x the subject of the formula c分之x=A=H.
c分之x=A=H
c分之x=A c分之x=H
x=Ac x=cH

3.Make m the subject of formula am-n=b
am-n=b
am=b+n
m=a分之b+n

4.Make x the subject of the formula 2ax=3b=s-y.
2ax=3b=s-y
2ax=3b 2ax=s-y
x=2a分之3b x=2a分之s-y

5.Make m the subject of the formula a(m-n)=7.
a(m-n)=7
am-an=7
am=7+an
m=a分之7+am

6.Make y the subject of the formula x=py=4ay.
x=py=4ay
x=py x=4ay
y=p分之x y=4a分之x

7.Make a the subject of the formula 2aw=-4y+6ah.
2aw=-4y+6ah
2aw-6ah=-4y
aw-3ah=-2y
a(w-3h)=-2y
a= - w-3h分之2y

8.Make y the subject of the formula p(x+y)=4ay.
p(x+y)=4ay
px+py=4ay
py-4ay=px
y(p-4a)=px
y=p-4a分之px

9.A=2WL+4HL [W]
A+4HL=2WL
W=2L分之A+4HL

10.9m-3m+2m=24
8m=24
m=3

11.5y-8=3y+14
5y-3y=8+14
2y=22
y=11

12.2y-18=8y+10
2y-8y=10+18
-6y=28
y=3分之14

13.7y-3=3(y+7)
7y-3=3y+21
7y-3y=21+3
4y=24
y=6

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