More STAAR problems.
Administered May 2017
Read each question carefully. For a multiple-choice question, determine the
best answer to the question from the four answer choices provided. For a
griddable question, determine the best answer to the question.
1. Which expression is equivalent to SQRT(147)?
A 3 SQRT(7)
B 7 SQRT(3)
C 21 SQRT(7)
D 49 SQRT(3)
Answer: 7 SQRT(3)
Factor the number in the square root, and pair the like factors up.
SQRT(147) = SQRT(3 * 7 * 7) = 7 SQRT(3)
The square root of 49 is 7, and 49 is a factor of 149, so it can be separated and rooted.
Which system of equations models this situation if the drummer wrote d songs and the
guitarist wrote g songs?
2. A drummer and a guitarist each wrote songs for their band. The guitarist wrote 8 fewer than twice the number of songs that the drummer wrote. They wrote a total of 46 songs.
F g = 2d - 8 ; g + d = 46
G g = 8 - 2d ; g = 46 - d
H d = 2g - 8 ; d = 46 - g
J d = 8 - 2g ; d + g = 46
Answer: F g = 2d - 8 ; g + d = 46
Please understand why Choices F and H can be eliminated immediately. The first equation in both choices would work if there were a total of 8 songs written. Think of the difference of having $20 less than you had originally, and originally having $20 and spending some amount of money.
Translate guitarist wrote 8 fewer than twice the drummer into
g equals subtract 8 from two times d, or g = 2d - 8
The total output of the two writers is 46 is g + d = 46. That being said, the other ways it is written -- g = 46 - d and d = 46 - g -- are not incorrect.
3. Which graph best represents the solution set of y ≤ -4x?
Answer: C
The ≤ symbol tells us that we will be shading underneath a solid line. The -4 cofficient of x tells us that it is a steep slope down and to the right.
That is Choice C. Choices A and D have the line y = -4, not y = -4x. Choice B has a broken line and is graphed above.
4. The graph of f(x) = x2 was transformed to create the graph of
g(x) = (x - 7.5)2. Which of
these describes this transformation?
F A horizontal shift to the right 7.5 units
G A horizontal shift to the left 7.5 units
H A vertical shift down 56.25 units
J A vertical shift up 56.25 units
Answer: F A horizontal shift to the right 7.5 units
This is pretty much a definition question, but you could graph them both in your calcultor and see the shift.
The vertex of a parabola is at the point (h, k) in the formula
Had the 7.5 been the k instead of the h, the graph would have shifted up or down, but only by 7.5 spaces.
What is the range of the function for this situation?
5. A set of weights includes a 4 lb barbell and 6 pairs of weight plates. Each pair of plates weighs 20 lb. If x pairs of plates are added to the barbell, the total weight of the barbell and plates in
pounds can be represented by f(x) = 20x + 4.
A {0, 1, 2, 3, 4, 5, 6}
B {4, 24, 44, 64, 84, 104, 124}
C {0, 2, 4, 6}
D {4, 44, 84, 124}
Answer: C
The range is the output, the dependent variable, the f(x) values, y. All that.
If the valid inputs are 0, 1, 2, 3, 4, 5, 6 because you can you that many pairs of weights, then the outputs are 4, 24, 44, 64, 84, 104, 124.
Choice A is the Domain. Choice C is the domain if you misread the question concerning the pairs of weights. Choice D is the range if you misread the question regarding pairs of weights.
More to come. Comments and questions welcome.
More STAAR problems.
No comments:
Post a Comment