I need help with #10!

#10. In three years, chad will be three times my present age. I will then be half as old as old as he. how old am I ?

6 years old.

Step-by-step explanation:

For this exercise let "x" represents your present age.

According to the information provided in the exercise, you know that  In three years, Chad will be three times your present age.

Then, your age in three years can be represented with the following expression:

Knowing at that time Chad's age will be three times yours and you will be half as old as old as Chad, you can write the following equation to represent this situation:

Therefore, the final step is to solve for "x" in order to find its value.

You get that this is:

(sin 42)/31. = sinx)/37

sinx = 37 (sin42)/31

= 37× 0.66/31 = 0.787

x= 51.9

other angle opposite to y = 180-51.9-42

= 180- 93.9 =86.1

so

sin42)/31 = sin 86.1)/y

0.021 = 0.997 /y

y= 0.997/0.021 =47.47