Respuesta :

Answer:

9. x=10

10. x=8

11. x=9/4=2.25

12. x=28

13. x=14

14. x=35

15. x=66

16. x=77/6

Step-by-step explanation:

9. x/20=18/36

Simplifying the fraction on the right side of the equation, dividing the numerator and denominator by 18:

x/20=(18/18) / (36/18)

x/20=1/2

Solving for x: Multiplying both sides of the equation by 20:

20(x/20)=20(1/2)

x=10


10. x/12=6/9

Simplifying the fraction on the right side of the equation, dividing the numerator and denominator by 3:

x/12=(6/3) / (9/3)

x/12=2/3

Solving for x: Multiplying both sides of the equation by 12:

12(x/12)=12(2/3)

x=4(2)

x=8


11. x/3=3/4

Solving for x: Multiplying both sides of the equation by 3:

3(x/3)=3(3/4)

x=9/4=2.25


12. x/42=30/45

Simplifying the fraction on the right side of the equation, dividing the numerator and denominator by 15:

x/42=(30/15) / (45/15)

x/42=2/3

Solving for x: Multiplying both sides of the equation by 42:

42(x/42)=42(2/3)

x=14(2)

x=28


13. x/12=14/12

Simplifying the fraction on the right side of the equation, dividing the numerator and denominator by 2:

x/12=(14/2) / (12/2)

x/12=7/6

Solving for x: Multiplying both sides of the equation by 12:

12(x/12)=12(7/6)

x=2(7)

x=14


14. x/25=28/20

Simplifying the fraction on the right side of the equation, dividing the numerator and denominator by 4:

x/25=(28/4) / (20/4)

x/25=7/5

Solving for x: Multiplying both sides of the equation by 25:

25(x/25)=25(7/5)

x=5(7)

x=35


15. x/110=(160-100)/100

x/110=60/100

Simplifying the fraction on the right side of the equation, dividing the numerator and denominator by 20:

x/110=(60/20) / (100/20)

x/110=3/5

Solving for x: Multiplying both sides of the equation by 110:

110(x/110)=110(3/5)

x=22(3)

x=66


16. x/11=(x+7)/17

Solving for x: Cross Multiplication:

17x=11(x+7)

Eliminating the parentheses on the right side of the equation:

17x=11(x)+11(7)

Multiplying:

17x=11x+77

Grouping the x's on the left side of the equation: Subtracting 11x both sides of the equation:

17x-11x=11x+77-11x

Subtracting:

6x=77

Dividing both sides of the equation by 6:

6x/6=77/6

Dividing:

x=77/6