Answer: Yes, the point (3,4) is a solution to the system.
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Proof of this:
Replace x with 3 and y with 4 in the first equation
x+y = 7
3+4 = 7
7 = 7
This confirms the first equation. Repeat for the second equation
x-2y = -5
3-2(4) = -5
3 - 8 = -5
-5 = -5
We get true equations for both when we plug in (x,y) = (3,4). This confirms it is a valid solution to the system of equations. It turns out it's the only solution to this system of equations. Visually, the two lines cross at the single location (3,4).
Answer:
the square of 96 by division method is

Let S = spoon
Let K = knife
1 knife is thee times the cost of a spoon, so it would be 3S
Now you have 9S + 12K = 82.80
We can replace the K with 3S:
9S +12(3S) = 82.80
Simplify the left side:
9S + 36S = 82.80
Add:
45S = 82.80
Divide both sides by 45"
S = 82.80 / 45
S = 1.84
One spoon cost $1.84
We know one knife cost 3 times as much, so multiply the cost of a spoon by 3:
Knife = 1.84 x 3 = $5.52