Respuesta :
Answer: C (Step 3)
Step-by-step explanation: In step 3, he did not subtract -7(9) to keep the function equivalent
Quadratic equations are second-order equations. Nick made In step 3 when he did not subtract –7(9) to keep the functional equivalent.
What is a Quadratic Equation?
A quadratic equation is an equation that can be written in the form of
ax²+bx+c.
Where a is the leading coefficient, and c is the constant.
In order to find the mistake that Nick made, we will first find the factors ourselves, therefore, we will factorize the trinomial,
[tex]17 \rm +42x-7x^2=9\\\\7x^2-42x+9-17=0\\\\7x^2-42x-11=0\\\\[/tex]
If we compare our process with Nick's process, we observe In step 3, he did not subtract –7(9) to keep the functional equivalent.
Hence, Nick made In step 3, when he did not subtract –7(9) to keep the functional equivalent.
Learn more about Quadratic Equations:
brainly.com/question/17177510
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