
Sarah M. answered 10/08/15
Tutor
5
(18)
Epidemiologist, Tutor, and Former Secondary (Grades 6-12) Math Teacher
"The sum of two numbers is 37.":
a+b=37
"The greater number [for us, let's say our greater number is b] is 5 more than [+] three times [*] the lesser number.":
b=5+3a
"What is the lesser of the two numbers?" We can find this by solving our system of equations:
a+b=37
b=5+3a Let's rearrange this equation so a and b are on the same side of the equal sign.
-3a+b=5
Now let's subtract our two equations
a+b=37
- [-3a+b= 5]
4a+0=32
Now, we can solve for a. (We already said b was the greater number, so that means a is the lesser number.)
4a=32
a=8
"What is the lesser of the two numbers?"
Answer: 8