Answers:
8. 12x+3= 27
move 3 to the other side , sign changes from +3 to -3
12x+3-3=27-3
12x= 24
divide by 12 for both sides
12x/12=24/12
x= 2
9. 6(y-10)=42
mutiply the bracket by 6
(6)(y)(6)(-10)= 6y-60
6y-60= 42
move -60 to the other side, sign changes from -60 to +60
6y-60+60=42+60
6y=102
divide by 6
6y/6=102/6
y=17
10. 9x-2=4x+13
move +4x to the other side
9x-4x-2= 4x-4x+13
5x-2= 13
5x-2+2= 13+2
5x= 15
divide by 5 for both sides
5x/5= 15/5
x= 3
11. 4/3y+5/2y= 1
find the common denominator for both of the fractions which is 6.
Mutiply by 2 for 4/3y .
4(2)/3(2)y=8/6y
Mutiply by 3 for 5/2y
5(3)/2(3y)= 15/6y
8/6y+15/6y= 23/6y
23/6y= 1
Mutiply both sides by 6/23
23/6y(6/23)= 1 (6/23)
Cross out 6 and 6 , divide by 6 and then becomes 1.
Cross out 23 and 23, divide by 23 and then becomes 1.
1*1*y=y
y= 6/23
Answer:
Robyn model makes more sense and Marks is nonsense.
Step-by-step explanation:
In this question ,calculations not required .All we have to do is consider each model logically .
Marks
Marks model shows 20 rather than 2 which means 200 is 10 times as much as 20. It does not make any sense.
Robyn
Robyn model shows 2 which means 200 is 100 times as much as 2 and this is not only correct but also makes sense because 100 *2=200
Answer:
3a -12
Step-by-step explanation:
3(– 2а - 4) + За → -6a - 12 + 3a → -3a -12
Answer:
Step-by-step explanation:
A) x/840=1/21
x=(1/21)*840=840/21=40
x=40
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B) 14/x=16/20
simplify 16/20 into 4/5
14/x=4/5
x=14/(4/5)=(14/1)(5/4)=70/4
simplify
x=35/2
Its E...........................................
