the difference between two number is 40. if their sum is 90, what are the numbers
Answers
The sum of x and y is 40. In other words, x plus y equals 40 and can be written as equation A:
x + y = 40
The difference between x and y is 90. In other words, x minus y equals 90 and can be written as equation B:
x - y = 90
Now solve equation B for x to get the revised equation B:
x - y = 90
x = 90 + y
Then substitute x in equation A from the revised equation B and then solve for y:
x + y = 40
90 + y + y = 40
90 + 2y = 40
2y = -50
y = -25
Now we know y is -25. Which means that we can substitute y for -25 in equation A and solve for x:
x + y = 40
x + -25 = 40
X = 65
Summary: The sum of two numbers is 40 and their difference is 90. What are the two numbers? Answer: 65 and -25 as proven here:
Sum: 65 + -25 = 40
Difference: 65 - -25 = 90
Answer:
The numbers are 65 and 25
Step-by-step explanation:
65 + 25 = 90
65 - 25 = 40