Answer:
Step-by-step explanation:
a). Given a parametric equation, we are describing a set of coordinates based on the value of t. The variable t is called the parameter.
b) we have the following equations. x=t y=t^2, so in order for us to know where the object is at t=t' we must replace t with the specific value t'. Hence, when t=0 the object is at (0,0^2) = (0,0) (the origin). When t=6, the object is at (6,6^2) = (6,36).
c). To eliminate the parameter, we replace the parameter in one equation by using the second equation. Recall that we have that x=t. Then, by replacing in the second equation, we have the following

where 
When a teacher gives a test with questions that fall into 3 levels of difficulty (easy, moderate, and hard) The scoring method that would best allow her to identify the students who need help is:
B. weight each question by its difficulty: 1 for easy, 2 for moderate, and 3 for hard.
Answer:
42/49 is the fraction
Step-by-step explanation:
you can't simplify so put the amount correct over the amount total.
<span>30x + 30y = 450 20x + 25y = 345
Here 345 represents the total area (in sq ft) shoveled; x repres. Melinda's rate and y represents Paul's rate. We need to solve for x and y and then subtract the smaller from the larger.
</span>30x + 30y = 450 Multiply this eqn by 2: 6<span>0x + 60y = 900
</span>20x + 25y = 345 Mult this eqn by -3: -60x -75y = -1035
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-15y = -135
y = 9
This comes to 9 square feet per minute.
Now, let's find x: 30x + 30y = 450; 30x + 270 = 450; 30x = 180; x = 6
Melinda can shovel 6 sq ft in 1 min, whereas Paul can shovel 9.
The difference is (9 - 6) sq ft / min, or 3 sq ft / min (answer)