A father is 4 times as old as his son. In 20 years the father will be twice as old as his son.. Find their present ages

x = the age of his son now, then the age of the father is 4x.

In 20 years,

son's age = x + 20

father's age = 4x + 20

solve the equation for x:

4x + 20 = 2(x + 20)

4x + 20 = 2x + 40

2x = 20

x = 10

So the age of his son now is 10, and the age of the the father now is 40.

hope it you

step-by-step explanation:

sin(7pi/6 - pi/3)  

= sin(7pi/6 - 2pi/6)  

= sin(5pi/6)  

= sin(pi - pi/6)  

= sin(pi/6)  

= 1/2  

sin 7pi/6 - sin pi/3  

= sin (pi + pi/6) - sin pi/3  

= -sin pi/6 - sin pi/3  

= -1/2 - sqrt(3)/2  

= -(1+sqrt(3))2

answer: 2 answers

step-by-step explanation: the first one means to spread the product throughout the marketplace such that a large number of people can buy it.  

the second means the process of making a product or service available for the consumer or business user that needs it.

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