The number of positive roots is the number of changes of signs there are, then decrease by 2 each time and stop when you get to 1 or 0
negative roots, sub every x with -x and reevaluate, count change of signs
decrease by 2 each time and stop when you get to 1 or 0
y=+2x⁵-x⁴-2x³+4x²+x-2
+,-,-,+,+,-
1 2 3
3 or 1 positive roots
replace x with -x ( baically flip all signs of odd powerd numbers)
y=-2x⁵-x⁴+2x³+4x²-x-2
-,-,+,+,-,-
1 2
2 or 0 negative roots
3 or 1 positive roots
2 or 0 negative roots
2nd option is answer
Answer:
x + 2(2x-4) = 10
Step-by-step explanation:
Here in this question, we want to select which is the correct answer if we substitute for the value of y in the second equation, using the first.
In the first, we have;
y = 2x -4
Now, let’s input this value of y into the second equation.
By direct substitution, what we have is the following;
x + 2y = 10
—-> x + 2(2x -4) = 10
Answer:
Positive and negative intervals on a graph
Step-by-step explanation:
The positive regions of a function are those intervals where the function is above the x-axis. It is where the y-values are positive (not zero). The negative regions of a function are those intervals where the function is below the x-axis. It is where the y-values are negative (not zero). hope this helps you :)
