SOLUTION: Please help me with {{{ One number is one less than twice the other. Their product is 120 }}} I do not understand how to read word problems or how to set them up.

Algebra ->  Problems-with-consecutive-odd-even-integers -> SOLUTION: Please help me with {{{ One number is one less than twice the other. Their product is 120 }}} I do not understand how to read word problems or how to set them up.      Log On


   



Question 623318: Please help me with +One+number+is+one+less+than+twice+the+other.+Their+product+is+120+
I do not understand how to read word problems or how to set them up.

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
Two numbers: a & b
:
write an equation for each statement:
:
One number is one less than twice the other.
a = 2b - 1
:
Their product is 120
a * b = 120
Replace a with (2b-1)
b(2b-1) = 120
2b^2 - b = 120
2b^2 - b - 120 = 0
factors to
(2b + 15)(b - 8) = 0
two solutions, only one integer solution
b = 8
Find a
a = 2(8) - 1
a = 15
:
Two numbers, 15 and 8