Answer:
Choice C is correct
Step-by-step explanation:
The first step is to re-write the equations in exponential form.
The first equation can be written as;
since the base is 10 and 4 the exponent.
The second equation can be written as;

The second step is to make N the subject of the formula in both equations.
Solving for N from this equation
, yields;

Solving for N from the second equation
, yields;

Therefore;

I would choose the answer D
<h3>
Answer: G) -2</h3>
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Explanation:
I'm assuming you meant to say (a+y)^2 + 2y
Replace each copy of 'a' with 5. Replace each copy of 'y' with -3. Use PEMDAS to simplify.
(a+y)^2 + 2y
(5 + (-3))^2 + 2(-3)
(5-3)^2 + 2(-3)
(2)^2 + 2(-3)
4 + 2(-3)
4 - 6
-2
So (a+y)^2 + 2y = -2 when a = 5 and y = -3.
Answer:
2) y = x - 4
y = -x + 2
=> x - 4 = -x + 2
=> 2x = -6
=> x = -3
=> y = -3 - 4 = -7
3) y = 3x + 1
y = 5x - 3
=> 3x + 1 = 5x - 3
=> 2x = 4
=> x = 2
=> y = 3(2) + 1 = 7
4) 2x + y = 8 => y = -2x + 8
y = x - 7
=> -2x + 8 = x - 7
=> 3x = 15
=> x = 5
=> y = 5 - 7 = -2