Question 1100048
a + b = 70
a / b = 4


solve for a in the first equation to get a = 70 - b


replace a in the second equation to get (70 - b) / b = 4


(70 - b) / b is the same as 70/b - b/b.


second equation becomes 70/b - b/b = 4


since b/b = 1, formula becomes 70/b - 1 = 4


add 1 to both sides of the equation to get 70/b = 5


multiply both sides of the equation by b to get 70 = 5b


solve for b to get b = 70/5 = 14


when b = 14, a + b = 70 becomes a + 14 = 70


solve for a to get a = 70 - 14 = 56


you have a = 56 and b = 14.


a + b = 56 + 14 = 70
a / b = 56 / 14 = 4


solution is that the first number is 56 and the second number is 14.


it might have been easier to solve for a in the second equation.


your two equations are, once again:


a + b = 70
a / b = 4


solve for a in the second equation to get a = 4b


replace a in the first equation to get 4b + b = 70


solve for b to get b = 70/5 = 14.


same answer but with less pain.