SOLUTION: The difference of two numbers is 77. The second is 7 less than 5 times the first. What are the two numbers?
Can some one please help out with this question?
v/r
Jess
Question 147860: The difference of two numbers is 77. The second is 7 less than 5 times the first. What are the two numbers?
Can some one please help out with this question?
v/r
Jess Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! Let the two numbers be x & y
:
Write an equation for each statement:
:
"The difference of two numbers is 77."
x - y = 77
or
x = (y + 77)
;
" The second is 7 less than 5 times the first."
y = 5x - 7
:
What are the two numbers?
:
Substitute (y+77) for x in the above equation, find y:
y = 5(y+77) - 7
:
y = 5y + 385 - 7
:
y - 5y = 378
:
-4y = 378
y =
y = -94.5 is the 2nd number
:
then
x = -94.5 + 77
:
x = -17.5 is the 1st number
;
:
Check solution in the statement:
"The second is 7 less than 5 times the first."
-94.5 = 5(-17.5) - 7
-94.5 = -87.5 - 7; confirms our solutions
