Answer:
Lisa earned $247.50 for working 33 hours.
Step-by-step explanation:
WAY 1: proportional reasoning
7.50 x
------ = ----
1 h 33h
33 / 1 = 33
7.50 x 33 = 247.5
WAY 2: unit rate reasoning
7.50 per hour so x value of money for 33 h
7.50 x 33 = 247.5
Factor because if we have
yz=0 then we can assume y and/or z=0
so factor
so the easiest way is to find what 2 numbers add to -6 and multiply to get 9 so
we know that they must be both - because we must have x+x=(-) and x^2=+ so therefor they must be negative
factors of 9=3 and 3 so
-3 and -3
-3+-3=-6 perfect
(z-3)(z-3)=0
set each to zero
z-3=0
add 3
z=3
z=3 is the answer
Answer:
B. Stratified random sample is the correct answer
<h3>
Answer: -2w^2 + 25w = 25 or -2w^2 + 25w - 25 = 0</h3>
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Explanation:
Refer to the diagram below. The width is w. We have two opposite and parallel sides equal to this. The other two parallel congruent sides are L = 25-2w meters long. We start with the total amount of fencing, and then subtract off the two width values, so 25-w-w = 25-2w.
The area of the rectangle is
Area = length*width
Area = L*W
Area = (25-2w)*w
Area = 25w - 2w^2
Area = -2w^2 + 25w
Set this equal to the desired area (25 square meters) to get
-2w^2 + 25w = 25
and we can subtract 25 from both sides to get everything on one side
-2w^2 + 25w - 25 = 0
side note: The two approximate solutions of this equation are w = 1.0961 and w = 11.4039 (use the quadratic formula or a graphing calculator to find this)