Question

Round to the nearest tenth, if necessary. Question: z2 = 361
options:
A.) 18, –18
B.) 180.5, –180.5
C.) 19, –19
D.) 19

Answer 1

The answer is option C) 19,-19

Step-by-step explanation:

Given, z² = 361

To eliminate the square of z, take square root on both sides

z = √361

• The factor of 361 could not be an even number, since the last digit of 361 is odd. So, eliminate option A)
• The option B) is a larger number and it cannot be the answer. So, eliminate it.
• Try option C) works or not. (19)² = 19$\times$19 = 361 and (-19)² = -19$\times$-19 = 361.
• Therefore, z = √361 = ±19. option C) is the correct answer.