Note the squares...
13 is possible because it is a sum of two squares (integers) 9 + 4 .. use (0,3) & (2,0) ... get the square roots and place on different coordinate axes... for a simpler value.
but there is none for 15...
there is one for 18 ...
18 = 3^2 + 3^2 ... try (0,3) ,(3,0) , (3,6), (6,3).
Every ft on model is 16 ft in the actual
Y = kx
15 = -3k
k = -5
so if x = 4
y = kx
y = (-5) (4) = - 20
answer
<span>y = -20 when the x = 4.</span>
The exponent Marina should use for b is: D. 7.
<h3>How to Divide Exponents with the same Base?</h3>
When dividing, you subtract the exponents. I.e.
.
Using the rule, we would also subtract the exponents of b in the simplified expression. Thus:

Subtract the exponents
4 -(-3) = 4 + 3 = 7.
Therefore, the Maria should use the exponent b = 7.
Learn more about dividing exponents on:
brainly.com/question/2263967
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