x + x-21 = 39
the numbers are 9 and 30
The sum of two numbers is -39. One number is 21 less than the other
2 answers
a = first number
b = second number
One number is 21 less than the other means:
b = a - 21
The sum of two numbers is - 39 of course means:
a + b = - 39
Replace b with a - 21 in this equation
a + a - 21 = - 39
2 a - 21 = - 39
Add 21 to both sides
2 a = - 18
Divide both sides by 2
a = - 9
b = a - 21
b = - 9 - 21
b = - 30
- 30 is 21 less than - 9
and
- 9 + ( - 30 ) = - 9 - 30 = - 39
So the numbers are - 9 and - 30
b = second number
One number is 21 less than the other means:
b = a - 21
The sum of two numbers is - 39 of course means:
a + b = - 39
Replace b with a - 21 in this equation
a + a - 21 = - 39
2 a - 21 = - 39
Add 21 to both sides
2 a = - 18
Divide both sides by 2
a = - 9
b = a - 21
b = - 9 - 21
b = - 30
- 30 is 21 less than - 9
and
- 9 + ( - 30 ) = - 9 - 30 = - 39
So the numbers are - 9 and - 30