Practice Test 105 - Algebra 2

20 questions. Answer them in any order, then submit to see your score and every explanation.

  1. Find the linear function f(x)=mx+bf(x)=mx+b with slope m=−3m=-3 that passes through the point (2,5)(2,5). What is f(x)f(x)?
  2. A company's profit function is P(x)=−2x3+24x2−72x+50P(x) = -2x^3 + 24x^2 - 72x + 50, where xx represents the number of items produced (in hundreds) and P(x)P(x) is profit in thousands of dollars. Analyzing the end behavior and critical points, which statement best describes the company's long-term production strategy?
  3. Solve for xx using the inverse relationship: log⁡2(x)=6\log_2(x)=6.​
  4. Graph the polynomial function p(x)=(x+2)2(x−1)(x−3)p(x)=(x+2)^2(x-1)(x-3) showing all zeros (with whether the graph crosses or touches at each zero) and the correct end behavior.​
  5. Determine whether the system has no solution, one solution, or infinitely many solutions: {2x+y=54x+2y=10\begin{cases} 2x + y = 5\\ 4x + 2y = 10 \end{cases}
  6. A shipping company models the cost (in dollars) to ship a package with weight ww (in pounds) by C(w)=5+2w−1C(w)=5+2\sqrt{w-1}. In this context, packages must weigh at least 1 pound. What is the realistic domain for ww?
  7. Solve for xx: log⁡2(x)=4\log_2(x)=4.
  8. A student graphs two equations and observes that the lines are parallel. Which of the following systems could produce this result?
  9. Use the key conjugate property (a+bi)(a−bi)=a2+b2(a+bi)(a-bi)=a^2+b^2 to compute (4+3i)(4−3i)(4+3i)(4-3i). (This product is always real and equals the modulus squared.)
  10. A town's population is recorded every year. Year yy: 0, 1, 2, 3 Population P(y)P(y): 15000, 15600, 16224, 16872.96 Does the population show constant percent change? If so, what is the percent growth rate per year?​​
  11. Use synthetic division to find the quotient and remainder when P(x)=2x4+x3−3x2+4x−1P(x)=2x^4+x^3-3x^2+4x-1 is divided by (x−2).(x-2). Set up with c=2c=2 and coefficients 2,1,−3,4,−12,1,-3,4,-1. Read the quotient coefficients from the bottom row and the remainder as the last value (which equals P(2)P(2)). Which is correct?
  12. Solve the quadratic equation by factoring: x2−9x+20=0x^2 - 9x + 20 = 0.​
  13. Sound intensity level in decibels is modeled by dB=10log⁡10(II0)\text{dB}=10\log_{10}\left(\frac{I}{I_0}\right), where I0I_0 is a reference intensity. A sound has intensity 5000I05000I_0. Create an equation and find its decibel level. Round to the nearest tenth of a decibel and interpret the result.
  14. A town's population is 18,000 and grows by 4% each year. Which function models the population after tt years (with t=0t=0 now)?
  15. The solutions to the equation x2+bx+c=0x^2 + bx + c = 0 are x=3±2ix = 3 \pm 2i. What are the values of bb and cc?
  16. Find the modulus rr and a correct argument θ\theta (in degrees) for z=−3−iz=-\sqrt{3}-i, then write zz in polar form r(cos⁡θ+isin⁡θ)r(\cos\theta+i\sin\theta). Use r=a2+b2r=\sqrt{a^2+b^2} and θ=arctan⁡ ⁣(ba)\theta=\arctan\!\left(\frac{b}{a}\right) with quadrant adjustment.
  17. The graphs of y=f(x)y=f(x) and y=g(x)y=g(x) intersect at the point (a,b)(a,b). Which statement must be true and explains why the solution(s) to f(x)=g(x)f(x)=g(x) come from intersection points?
  18. A local theater charges a fixed rental fee plus an additional cost per hour for use of their facility. The total cost for renting the theater for 3 hours is $450, and for 7 hours is $750. Which equation represents the relationship between the total cost CC (in dollars) and the number of hours hh?
  19. What are q(x)q(x) and r(x)r(x) when x4−2x2+x+1x2+1\frac{x^4-2x^2+x+1}{x^2+1} is written as q(x)+r(x)x2+1q(x)+\frac{r(x)}{x^2+1} with deg⁡(r)<2\deg(r)<2 (as required by the polynomial division algorithm)?
  20. Express x3−4x2+x+6x−3\frac{x^3-4x^2+x+6}{x-3} as q(x)+r(x)x−3q(x)+\frac{r(x)}{x-3} using the polynomial division algorithm, with deg⁡(r)<deg⁡(x−3)\deg(r)<\deg(x-3).

Practice tests