1. Change x = 4t into x = 3t
so
Answer A and D are wrong.
2. Change x = 4t into x = 2t
and
Answer b is correct.
3. Change x = 4t into x = 8t
and
Answer C. is correct, E. is wrong.
Count change of signs to tell positive roots
then replace x with -x and evaluate, then count change in sign for negative roots
initially
+, -, -, +, +, -
3 changes
3 or 1 positive roots
replacing x with -x
-,-,+,+,-,-
2 changes
2 or 0 negative roots
B is answer
So if 6 out of 40 are incorrect, 40-6= 36 must be correct.
In order to gain percentage you do proportions.
36/40 = x/100.
Multiply 36 times 100 then divide by 40, which is 90.
The answer is 90%.
90% of the questions he got were correct.
<u>Answer:</u>
<u>The answer to five hundred million, one hundred fifteen in standard form is actually 500,000,115 because five hundred million in standard form is 500,000,000 and one hundred fifteen in standard form is 115.</u>
