"When the radicand equals zero" is the one among the following choices given in the question that you can tell when <span>a quadratic equation has two identical, rational solutions. The correct option among all the options that are given in the question is the fourth option or option "d". I hope the answer has helped you.</span>
Answer:

Step-by-step explanation:
In the decimal of −12,405, leave the −12 and divide 405 by 1000 for now:

Greatest Common Divisor [GCD]: 5
Finally, you attach this back to the −12, giving you
.
I am joyous to assist you anytime.
Easy, the second one. Both figures seem congruent.