math questions for algebra

Question

One number is four more than a second number. Two times the first number is 12 more than four times the second number. Find the two numbers?

Answer 1

a = 1st number

b = 2nd number

given info

a=4b

2a=4b+12

take 1 from the 1st equation and put it in the second

so

2*(4b)=4b+12

8b-4b=12

4b=12

b=3

so

a=4*3

a=12

Answer 2

X = Y+4

2x = 12 + 4y

2(y+4) = 12 + 4y

2y + 8 = 12 + 4y

8 = 12 + 2y

-4 = 2y

y = -2

x= -2 + 4 = 2

Indeed 2*2 = 4 = 12 + 4(-2) = 12 - 8