<em>Step #1: </em>
Make sure the equation is in the form of [ Ax² + Bx + C = 0 ].
Yours is already in that form.
A = 1
B = 2
C = -2
<em>Step #2:</em>
The 'discriminant' for that equation is [ B² - 4 A C ].
That's all there is to it, but it can tell you a lot about the roots of the equation.
-- If the discriminant is zero, then the left side of the equation is a perfect square,
and both roots are equal.
-- If the discriminant is greater than zero, the the roots are real and not equal.
-- If the discriminant is less than zero, then the roots are complex numbers.
The discriminant of your equation is [ B² - 4 A C ] = 2² - 4(1)(-2) = 4 + 8 = 12
Your equation has two real, unequal roots.
Going by the formula, Half-Life = ln(.5) / k
Half-Life = .693147 / .1205
Half-Life = 5.75 days and rounded to nearest tenth,
Half-Life = 5.8 days
It is unclear what you want to do, but in the case where they give you the length and the width, it is most likely they are asking for either area or perimeter. For Area, it is length times width.
A = l x w
A = 60 yards x 50 yards
A = 3000 square yards.
For Perimeter of the rectangle, it is 2 of the lengths plus 2 of the widths.
P = 2 ( 60 yards ) + 2 ( 50 yards )
P = 120 yards + 100 yards
P = 220 yards
I hope this helps :-)
The number of trucks needed is an illustration of rates
The number of trucks needed is 42
<h3>How to determine the number of trucks</h3>
The size of the backfill is given as: 243 CY
A truck can load up to 162 CF
So, the number of trucks needed is calculated as:

Convert CY to CF

Solve

Approximate

Hence, 41 trucks are needed
Read more about rates at:
brainly.com/question/8728504