in a 2-digit number, the the tens digit is 5 less than the units digit. if you reverse the number, the result is 7 greater than double the original. find the original number.

were is the equation

cross multiplying, we get :

⇒ (3) × (5) = (9) × (x)

⇒ 15 = 9x

6 adults and 9 children went.

a + c = 15

12a + 9c = 153

12(6) + 9(9) = 153

72 + 81 = 153

since no one answered yet i will give it a shot, not completely sure tho.

i think it should be y=cos(x+2pi), (third answer, answer c)

good luck.