Questions in mathematics

Questions in mathematics

[Free] Which of the following values are solutions to the inequality $-6-x \leq 7$? I. -13 II. -14 III. -6 A. None B. I only C. II only D. III only E. I and II F. I and III G. II and III H. I, II and III

[Free] Review the incomplete derivation of the cosine sum identity. | Step 1 | [tex]\cos (x+y)[/tex] | | :----- | :---------------------------------- | | Step 2 | [tex]$\sin \left(\frac{\pi}{2}-(x+y)\right)$[/tex] | | Step 3 | | | Step 4 | [tex]$\sin \left(\frac{\pi}{2}-x\right) \cos (y)-\cos \left(\frac{\pi}{2}-x\right) \sin (y)$[/tex] | | Step 5 | | Which expressions for Step 3 and Step 5 complete the derivation? A. Step 3: [tex]$\sin \left(\left(\frac{\pi}{2}-x\right)+y\right)$[/tex] Step 5: [tex]$\cos (x) \cos (y)+\sin (x) \sin (y)$[/tex] B. Step 3: [tex]$\sin \left(\left(\frac{\pi}{2}-x\right)+y\right)$[/tex] Step 5: [tex]$\cos (x) \cos (y)-\sin (x) \sin (y)$[/tex] C. Step 3: [tex]$\sin \left(\left(\frac{\pi}{2}-x\right)-y\right)$[/tex] Step 5: [tex]$\cos (x) \cos (y)+\sin (x) \sin (y)$[/tex] D. Step 3: [tex]$\sin \left(\left(\frac{\pi}{2}-x\right)-y\right)$[/tex] Step 5: [tex]$\cos (x) \cos (y)-\sin (x) \sin (y)$[/tex]

[Free] Solve the system of linear equations by graphing. [tex]\begin{array}{l} 2 x+3 y=16.9 \\ 5 x=y+7.4 \end{array}[/tex] What is the solution to the system of linear equations? Round to the nearest tenth as needed.

[Free] What is the constant of variation, [tex]$k$[/tex], of the direct variation, [tex]$y=k x$[/tex], through [tex]$(5,8)$[/tex] ? A. [tex]$k=-\frac{8}{5}$[/tex] B. [tex]$k=-\frac{5}{8}$[/tex] C. [tex]$k=\frac{5}{8}$[/tex] D. [tex]$k=\frac{8}{5}$[/tex]

[Free] Use the given conditions to write an equation for the line in point-slope form and slope-intercept form. Passing through $(-5,-5)$ and $(5,7)$ Type the point-slope form of the equation of the line. [tex]y+5=\frac{6}{5}(x+5)[/tex] (Use integers or simplified fractions for any numbers in the equation.) Type the slope-intercept form of the equation of the line. [tex]\square[/tex] (Use integers or simplified fractions for any numbers in the equation.)

[Free] Solve for t. [tex]e^{-0.24 t}=0.59[/tex]

[Free] If 15% of adults in a certain country work from home, what is the probability that fewer than 54 out of a random sample of 450 adults will work from home? (Round your final answer to 4 decimal places.)

[Free] Henry shows potential cities he could visit, as well as what he estimates it will cost him to visit each one. All costs are given in grazilian reals (RS). | City | Cost (RS) | | ---------------- | --------- | | Salvador | 224 | | Duque de Caxias | 242 | | Rio de Janeiro | 193 | | Campinas | 185 | | Porto Alegre | 153 | | Guarulhos | 120 | | Fortaleza | 201 | Henry's original plan was to visit Duque de Caxias, Campinas, Rio de Janeiro, and Guarulhos. However, he only has R$699 to spend, so he cannot afford to use his original itinerary. Which of the following changes will be the cheapest swap Henry can make and still come in under budget? A. Replace Duque de Caxias with Salvador. B. Replace Duque de Caxias with Fortaleza.

[Free] Use a graphing calculator to sketch the graph of the quadratic equation, and then state the domain and range. [tex]y=-0.5 x^2+0.7 x-5.1[/tex] a. D: all real numbers R: [tex](y \leq-5.1)[/tex] b. D: all real numbers R: [tex](y \geq 4.855)[/tex] c. D: all real numbers R: [tex](y \leq-4.855)[/tex] d. D: all real numbers R: [tex](y \leq-5.345)[/tex] Please select the best answer from the choices provided

[Free] Let [tex]\mathbf{u} = \overrightarrow{XY}[/tex] where X = (-4, 6) and Y = (8, 3). What is the magnitude of 2[tex]\mathbf{u}[/tex]?