Solve the equation by the zero-factor property. \( 2 x^{2}=-21 x-49 \) \( \{-7,-14\} \) \( \left\{7,-\frac{7}{2}\right\} \) \( \left\{7, \frac{7}{2}\right\} \) \( \left\{-\frac{7}{2},-7\right\} \)

Determine which ordered pair(s) are solutions to the following system. \[ \begin{array}{lll}y=4 x-2 \\ y=-x+23 & (5,18) & (3,-10)\end{array}(2,21) \]

A. \( 4 x^{2} y\left(x z^{2}+5 w x y+3\right) \).

23. Reasoning Twenty of the students in Hannah's class, or \( 80 \% \) of the class, voted to have pizza fol lunch every Wednesday. How many students are in Hannah's class?

b. Two consecufive number are sucl that the sum of thrice the smaller and twice the larger is 17. Find, correct to three significant figures the smaller number as a percen - tage of the sum of the. two numbers.

(a) Find the solution for \( |2 x+1|+3=5 \). Select the correct choice below, and fill in the answer box if necessary. A. The solution set is the finite set of real numbers \( \{ \). (Simplify your answer. Use integers or fractions for any numbers in the expression. Use a comma to separate answers as needed.) B. The solution set is the interval (Type your answer in interval notation. Use integers or fractions for any numbers in the expression.)