Sorry I need help again. There is no example for this problem. I know the two answers are 8 and 12 but I don't know how to put that in an equation.
The sum of two numbers is 20. Their difference is 4.
a. Write a system of equations that describes this situation.
b. Solve by elimination to find the two numbers.
2007-01-29 13:23:47 · 3 answers · asked by Anonymous in Education & Reference ➔ Homework Help
system of equations:
x+y=20
x-y=4
add the columns, the y's cancel because they are a positive and a negative, (this is substitution)
so:2x=24
x=12, so y must =8
chantel.......you're way wrong, in answers and equation
2007-01-29 13:28:43 · answer #1 · answered by ?s @ Y! Answers 3 · 1⤊ 1⤋
20-12=8
20-8=12
12-8=4
Check:
12+8 = 20
2007-01-29 21:27:41 · answer #2 · answered by May 4 · 1⤊ 0⤋
x+y=20
x-y=4
-------------
add them
2x=16
x=8
substitute that back into the equation
y=12
2007-01-29 21:30:06 · answer #3 · answered by Anonymous · 1⤊ 1⤋