3% interest on 5,000 = 150
275 (the total amount wanted) - 150 (from initial investment)= 125
x (5%) =125
x (0.05)= 125
x/0.05)= 125/0.05
x=2500
you need to invest 2500 at 5% to get the additional 125
125 plus 150= 275
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).
Average speed is given by [Total Distance] ÷ [Total Time]
Average speed =

km/hour
Yo sup??
we can simply try option verification for this problem.
when x=0 we get,
1 and 1≠5 therefore x=0 is not a solution.
when x=1 we get
√6-1≠5 therefore x=1 is not a solution.
when x=16 we get
9-4=5 therefore x=16 is a solution
Hence the correct answer is option C
Hope this helps.