Fix the Two Roots, Not One Mistake

Understand the problem

1 of 3

First, understand the question

Do not start calculating until the given information and the required answer are clear.

Problem

Solve 9x2−16=09x^2-16=0.

What are we trying to do?

Find every value of xx that makes 9x2−169x^2-16 equal to zero.

Build the solution one reason at a time

Read why each action is needed. Then use it to change the mathematical model.

9x2−16=09x^2-16=0
3x−4=0⇒x=433x-4=0\Rightarrow x=\frac43
3x+4=0⇒x=−433x+4=0\Rightarrow x=-\frac43

Both branches matter.

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