Step-by-step explanation:
(2x-y+3)(2x-y-3)=
4x²-2xy-6x-2xy+y²+3y+6x-3y-9=
4x²-4xy+y²-9=
(2x-y)²-9
X+3y=7
x-3y=1
add them together
x+3y=7
<u>x-3y=1 +
</u>2x+0y=8
2x=8
divide 2
x=4
subsitute
x+3y=7
4+3y=7
subtract 4
3y=3
divid 3
y=1
x=4
y=1
answer is A
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Answer:
15 hours
Step-by-step explanation:
To find the gallons per hour: 230/5=46, this means that it take 46 gallons per hour, you add 46 to 230, and you do that 15 times and you'll get 920. The pool will be filled at 11:00 pm.
C. they are worth the same amount of money, 1/2 and 2/4 are both 50% or 50 cents
Legnth of 1 section times number of sections=number of feet needed=6*12=72
72ft=850
divie both sides by 72
1ft=11.8055555
1 ft=$11.81
