Choose the statement that correctly completes this sentence: If a and b are real numbers, then the product of a + bi and a -bi is

The parabola y = x² - 4 opens: a.) up b.) down c.) right d.) left

To solve the system of equations below, pedro isolated the variable y in the first equation and then substituted it into the second equation. what was the resulting equation? { 5y=10x {x^2+y^2=36

Acollection of coins has value of 64 cents. there are two more nickels than dimes and three times as many pennies as dimes in this collection. how many of each kind of coin are in the collection?