Reflection across the x-axis:
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y = − f ( x ) y = -f(x) y=−f(x) The concept behind the reflections about the x-axis is basically the same as the reflections about the y-axis.
Answer:
Prime
Step-by-step explanation:
x² + 20x − 36
You must find a pair of numbers that multiply to give -36 and add to give +20.
The likely candidates are 2 and 18, and they must have opposite signs to give a negative product.
+2 × (-18) = -36; +2 + (-18) = -16
-2 × 18 = -36; -2 + 8 = +16
Neither combination gives +20 as the sum.
The expression can't be factored with rational numbers.
The expression is prime.
Are you sure this is written correctly. It is not factorable as it is