- Quadratic Formula:
, with a = x^2 coefficient, b = x coefficient, and c = constant
With our equation, plug in the values:

Next, solve the exponent and multiplications:

Next, solve the subtraction:

Next, factor out i (i = √-1):

Next, solve the square root:

Lastly, divide and <u>your answer is:</u>

6-3=3, so m=3. Easy as pie
Total gasoline = 10 gallons
Gasoline left after 100 miles = 5 gallons
Gasoline used in 100 miles
= Total gasoline - Gasoline left after 100 miles
= 10 gallons - 5 gallons
= 5 gallons
Gasoline used in 1 mile
= Gasoline used in 100 miles/100
= 5 gallons/100
= 0.05 gallons
85 x 3 = 255
first 2 test grades were 81 and 86:
81 + 86 = 167
Need to find the 3rd to have exact average 85:
255 - 167 = 88
So her 3rd test needs to make 88 to make average of 85
Double check: 81 + 86 + 88 = 255 = 85 + 85 + 85