1) b^2 - 4ac = ( -2 )^2 - 4×( 0.5 ) × 2 = 4 - 4 = 0;
2) b^2 - 4ac =( -5)^2 - 4×2×20 = 25 - 160 = - 135 ;
$2.00 cause imagine she has 6 dollar 2/3 is 4.00 so it's 2.00
Answer: 
Step-by-step explanation:
You need to remember the mulplication of signs:

Knowing this, you can distributive the negative sign. Then you get:

Now you need to add the like terms. Then:

Finally, you can order the polynomial obtained in descending order. Therefore, the answer is:

When rates expressed as a quantaty of 1, such as 2 feet per second or 5 miles per hour
Just do for example on number 38 you will do 6.8/1000= 0.0068 which is the answer