Answer:
x = -28 and y = -21
Step-by-step explanation:
Let two numbers be x and y.
One number is seven less than a second number.
x = y-7
x-y = -7 ...(1)
Three times the first is three more than four times the second.
3x = 4y or
3x-4y =0 ...(2)
Multiplying equation (1) by 3. So,
3x-3y = -21 ...(3)
Subtracting equation (2) from (3).
3x-3y-(3x-4y) = -21
-3y+4y = -21
y = -21
Put the value of y in equation (1).
x-(-21)= -7
x+21=-7
x = -21-7
x = -28
So, the value of x and y are -28 and -21 respectively.