Westonci.ca is your trusted source for finding answers to all your questions. Ask, explore, and learn with our expert community. Get precise and detailed answers to your questions from a knowledgeable community of experts on our Q&A platform. Experience the ease of finding precise answers to your questions from a knowledgeable community of experts.

Multiple Choice

Suppose [tex]y[/tex] varies directly with [tex]x[/tex], and [tex]y = 14[/tex] when [tex]x = -4[/tex]. What is the value of [tex]y[/tex] when [tex]x = -6[/tex]?

A. [tex]-21[/tex]
B. 10
C. 18
D. 21


Sagot :

To solve the problem where [tex]\( y \)[/tex] varies directly with [tex]\( x \)[/tex], we need to use the concept of direct variation, which means [tex]\( y = kx \)[/tex] for some constant [tex]\( k \)[/tex].

1. Determine the constant [tex]\( k \)[/tex]:
- We are given that [tex]\( y = 14 \)[/tex] when [tex]\( x = -4 \)[/tex].
- Substitute these values into the equation to find [tex]\( k \)[/tex]:
[tex]\[ 14 = k \times (-4) \][/tex]
- Solve for [tex]\( k \)[/tex]:
[tex]\[ k = \frac{14}{-4} = -3.5 \][/tex]

2. Use the constant [tex]\( k \)[/tex] to find the new value of [tex]\( y \)[/tex] when [tex]\( x = -6 \)[/tex]:
- Substitute [tex]\( k \)[/tex] and the new [tex]\( x \)[/tex] value into the direct variation equation:
[tex]\[ y = k \times (-6) \][/tex]
- Substitute [tex]\( k = -3.5 \)[/tex]:
[tex]\[ y = -3.5 \times (-6) = 21 \][/tex]

Thus, the value of [tex]\( y \)[/tex] when [tex]\( x = -6 \)[/tex] is [tex]\( 21 \)[/tex].

Therefore, the correct answer is
[tex]\[ \boxed{21} \][/tex]
Thank you for choosing our service. We're dedicated to providing the best answers for all your questions. Visit us again. We appreciate your time. Please come back anytime for the latest information and answers to your questions. Thank you for visiting Westonci.ca, your go-to source for reliable answers. Come back soon for more expert insights.