1.69 is 1.3 to the second power
Answer:

Step-by-step explanation:
The sum you are trying to understand is this.

Remember that in general when you have a geometric series
you have that
and that equality is true as long as
.
Therefore here we have
and 
Therefore we can use the formula and

1. A quadratic equation has the following form: ax²+bx+c.
2. The leading coefficient is the number that is attached to the variable with the highest exponent. Then, the "a" is the leading coefficient of the quadratic equation.
3. The problem says that the leading coefficient is 1 (a=1) and the roots of the quadratic equation are 5 and -3. Then, you have:
(x-5)(x+3)=0
4. When you apply the distributive property, you obtain:
x²+3x-5x-15=0
x²-2x-15=0
5. Therefore, the answer is:
x²-2x-15=0
Answer:
D
Step-by-step explanation: