Answer:
20/9
Step-by-step explanation:
80 40 20
--- = ------- = -------
36 18 9
find the gcf of the numerator and denominator. then simply it till you can't.

The property that justifies multiplying through eqn(2) by -2 is;
the rationalization to align the coefficients of x in both equations with a view to eliminating the terms in x.
5x+7y=25
5x-2y=-65
subtract both of the equations
5x-5x=0
7y--2y= 7y+2y=9y
25--65=25+65=90
0+9y=90
9y=90
divide both sides by 9 to get y by itself
9y/9=90/9
cross out 9 and 9 which becomes 1*1*y=y
90/9=10
y=10
find x by using the substitution method
5x+7y=25
5x+7(10)=25
5x+70=25
move +70 to the other side
sign changes from +70 to -70
5x+70-70=25-70
5x=-45
divide both sides by 5 to get x by itself
5x/5=-45/5
cross out 5 and 5 then becomes 1*1*x=x
-45/5=-9
x=-9
answer:
(-9,10)
How many batteries are in a pack?
You would take that number and divide it by 8.34. That would give you the price per battery. From there you can figure out how many batteries you can buy with only $3 and how much money would be left over.
Answer:
5/12
Step-by-step explanation: